On a checkout from June 16, I get this crash on iPad when entering/leaving the tab switcher with multiple tabs open, multiple times.
I don't have the exact steps to reproduce, but the crash happens relatively quickly.

2017-06-21 12:32:24.467 Chromium[61114:388732] *** Assertion failure in -[UICollectionView _endItemAnimationsWithInvalidationContext:tentativelyForReordering:animator:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3600.6.21/UICollectionView.m:5634
2017-06-21 12:32:24.564 Chromium[61114:388732] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of items in section 1.  The number of items contained in an existing section after the update (8) must be equal to the number of items contained in that section before the update (6), plus or minus the number of items inserted or deleted from that section (1 inserted, 1 deleted) and plus or minus the number of items moved into or out of that section (0 moved in, 0 moved out).'
*** First throw call stack:
(
	0   CoreFoundation                      0x000000010ea86d4b __exceptionPreprocess + 171
	1   libobjc.A.dylib                     0x00000001131bc21e objc_exception_throw + 48
	2   CoreFoundation                      0x000000010ea8ae42 +[NSException raise:format:arguments:] + 98
	3   Foundation                          0x000000010f87466d -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 195
	4   UIKit                               0x000000010daa2293 -[UICollectionView _endItemAnimationsWithInvalidationContext:tentativelyForReordering:animator:] + 17367
	5   UIKit                               0x000000010da9dce1 -[UICollectionView _updateRowsAtIndexPaths:updateAction:] + 377
	6   Chromium                            0x000000010259a25a -[GoogleLandingViewController mostVisitedIconMadeAvailableAtIndex:] + 234
	7   Chromium                            0x000000010258be67 -[GoogleLandingMediator onIconMadeAvailable:] + 215
	8   Chromium                            0x0000000102a23ec1 _ZN9ntp_tiles30MostVisitedSitesObserverBridge19OnIconMadeAvailableERK4GURL + 81
	9   Chromium                            0x0000000106950a73 _ZN9ntp_tiles16MostVisitedSites19OnIconMadeAvailableERK4GURL + 51
	10  Chromium                            0x000000010695943d _ZN4base8internal13FunctorTraitsIMN9ntp_tiles16MostVisitedSitesEFvRK4GURLEvE6InvokeIPS3_JS6_EEEvS8_OT_DpOT0_ + 141
	11  Chromium                            0x000000010695939f _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKMN9ntp_tiles16MostVisitedSitesEFvRK4GURLEJPS5_S8_EEEvOT_DpOT0_ + 95
	12  Chromium                            0x000000010695932d _ZN4base8internal7InvokerINS0_9BindStateIMN9ntp_tiles16MostVisitedSitesEFvRK4GURLEJNS0_17UnretainedWrapperIS4_EES5_EEEFvvEE7RunImplIRKS9_RKNSt3__15tupleIJSB_S5_EEEJLm0ELm1EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEE + 125
	13  Chromium                            0x000000010695923c _ZN4base8internal7InvokerINS0_9BindStateIMN9ntp_tiles16MostVisitedSitesEFvRK4GURLEJNS0_17UnretainedWrapperIS4_EES5_EEEFvvEE3RunEPNS0_13BindStateBaseE + 44
	14  Chromium                            0x000000010203ae3d _ZNKR4base8CallbackIFvvELNS_8internal8CopyModeE1ELNS2_10RepeatModeE1EE3RunEv + 61
	15  Chromium                            0x0000000106941c22 _ZN9ntp_tiles14IconCacherImpl35FinishRequestAndNotifyIconAvailableERK4GURLb + 1170
	16  Chromium                            0x0000000106942409 _ZN9ntp_tiles14IconCacherImpl31OnPopularSitesFaviconDownloadedENS_12PopularSites4SiteENSt3__110unique_ptrIN4base18CancelableCallbackIFvRKN3gfx5ImageEEEENS3_14default_deleteISC_EEEERKNS3_12basic_stringIcNS3_11char_traitsIcEENS3_9allocatorIcEEEESA_RKN13image_fetcher15RequestMetadataE + 345
	17  Chromium                            0x0000000106944892 _ZN4base8internal13FunctorTraitsIMN9ntp_tiles14IconCacherImplEFvNS2_12PopularSites4SiteENSt3__110unique_ptrINS_18CancelableCallbackIFvRKN3gfx5ImageEEEENS6_14default_deleteISE_EEEERKNS6_12basic_stringIcNS6_11char_traitsIcEENS6_9allocatorIcEEEESC_RKN13image_fetcher15RequestMetadataEEvE6InvokeIPS3_JRKS5_SH_SP_SC_ST_EEEvSV_OT_DpOT0_ + 770
	18  Chromium                            0x0000000106944553 _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKMN9ntp_tiles14IconCacherImplEFvNS4_12PopularSites4SiteENSt3__110unique_ptrINS_18CancelableCallbackIFvRKN3gfx5ImageEEEENS8_14default_deleteISG_EEEERKNS8_12basic_stringIcNS8_11char_traitsIcEENS8_9allocatorIcEEEESE_RKN13image_fetcher15RequestMetadataEEJPS5_RKS7_SJ_SR_SE_SV_EEEvOT_DpOT0_ + 195
	19  Chromium                            0x000000010694438b _ZN4base8internal7InvokerINS0_9BindStateIMN9ntp_tiles14IconCacherImplEFvNS3_12PopularSites4SiteENSt3__110unique_ptrINS_18CancelableCallbackIFvRKN3gfx5ImageEEEENS7_14default_deleteISF_EEEERKNS7_12basic_stringIcNS7_11char_traitsIcEENS7_9allocatorIcEEEESD_RKN13image_fetcher15RequestMetadataEEJNS0_17UnretainedWrapperIS4_EES6_NS0_13PassedWrapperISI_EEEEEFvSQ_SD_SU_EE7RunImplIRKSW_RKNS7_5tupleIJSY_S6_S10_EEEJLm0ELm1ELm2EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEESQ_SD_SU_ + 299
	20  Chromium                            0x00000001069441df _ZN4base8internal7InvokerINS0_9BindStateIMN9ntp_tiles14IconCacherImplEFvNS3_12PopularSites4SiteENSt3__110unique_ptrINS_18CancelableCallbackIFvRKN3gfx5ImageEEEENS7_14default_deleteISF_EEEERKNS7_12basic_stringIcNS7_11char_traitsIcEENS7_9allocatorIcEEEESD_RKN13image_fetcher15RequestMetadataEEJNS0_17UnretainedWrapperIS4_EES6_NS0_13PassedWrapperISI_EEEEEFvSQ_SD_SU_EE3RunEPNS0_13BindStateBaseESQ_SD_SU_ + 111
	21  Chromium                            0x00000001065912f0 _ZNKR4base8CallbackIFvRKNSt3__112basic_stringIcNS1_11char_traitsIcEENS1_9allocatorIcEEEERKN3gfx5ImageERKN13image_fetcher15RequestMetadataEELNS_8internal8CopyModeE1ELNSJ_10RepeatModeE1EE3RunES9_SD_SH_ + 112
	22  Chromium                            0x00000001065910e5 _ZN13image_fetcher16ImageFetcherImpl14OnImageDecodedERK4GURLRKNS_15RequestMetadataERKN3gfx5ImageE + 1349
	23  Chromium                            0x000000010659557d _ZN4base8internal13FunctorTraitsIMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNS2_15RequestMetadataERKN3gfx5ImageEEvE6InvokeIPS3_JS6_S9_SD_EEEvSF_OT_DpOT0_ + 173
	24  Chromium                            0x000000010659549a _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNS4_15RequestMetadataERKN3gfx5ImageEEJPS5_S8_SB_SF_EEEvOT_DpOT0_ + 138
	25  Chromium                            0x00000001065953fc _ZN4base8internal7InvokerINS0_9BindStateIMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNS3_15RequestMetadataERKN3gfx5ImageEEJNS0_17UnretainedWrapperIS4_EES5_S8_EEEFvSE_EE7RunImplIRKSG_RKNSt3__15tupleIJSI_S5_S8_EEEJLm0ELm1ELm2EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEESE_ + 204
	26  Chromium                            0x00000001065952b4 _ZN4base8internal7InvokerINS0_9BindStateIMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNS3_15RequestMetadataERKN3gfx5ImageEEJNS0_17UnretainedWrapperIS4_EES5_S8_EEEFvSE_EE3RunEPNS0_13BindStateBaseESE_ + 68
	27  Chromium                            0x0000000102380bdd _ZNKR4base8CallbackIFvRKN3gfx5ImageEELNS_8internal8CopyModeE1ELNS6_10RepeatModeE1EE3RunES4_ + 77
	28  Chromium                            0x000000010238087d _ZN13image_fetcher19IOSImageDecoderImpl27CreateUIImageAndRunCallbackERKN4base8CallbackIFvRKN3gfx5ImageEELNS1_8internal8CopyModeE1ELNS8_10RepeatModeE1EEEP6NSData + 157
	29  Chromium                            0x000000010238069e _ZN13image_fetcher19IOSImageDecoderImpl11DecodeImageERKNSt3__112basic_stringIcNS1_11char_traitsIcEENS1_9allocatorIcEEEERKN3gfx4SizeERKN4base8CallbackIFvRKNSA_5ImageEELNSE_8internal8CopyModeE1ELNSK_10RepeatModeE1EEE + 1166
	30  Chromium                            0x0000000106590ad4 _ZN13image_fetcher16ImageFetcherImpl17OnImageURLFetchedERK4GURLRKNSt3__112basic_stringIcNS4_11char_traitsIcEENS4_9allocatorIcEEEERKNS_15RequestMetadataE + 1156
	31  Chromium                            0x0000000106594cfd _ZN4base8internal13FunctorTraitsIMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNSt3__112basic_stringIcNS7_11char_traitsIcEENS7_9allocatorIcEEEERKNS2_15RequestMetadataEEvE6InvokeIPS3_JS6_SF_SI_EEEvSK_OT_DpOT0_ + 173
	32  Chromium                            0x0000000106594c1a _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNSt3__112basic_stringIcNS9_11char_traitsIcEENS9_9allocatorIcEEEERKNS4_15RequestMetadataEEJPS5_S8_SH_SK_EEEvOT_DpOT0_ + 138
	33  Chromium                            0x0000000106594b80 _ZN4base8internal7InvokerINS0_9BindStateIMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNSt3__112basic_stringIcNS8_11char_traitsIcEENS8_9allocatorIcEEEERKNS3_15RequestMetadataEEJNS0_17UnretainedWrapperIS4_EES5_EEEFvSG_SJ_EE7RunImplIRKSL_RKNS8_5tupleIJSN_S5_EEEJLm0ELm1EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEESG_SJ_ + 160
	34  Chromium                            0x0000000106594a74 _ZN4base8internal7InvokerINS0_9BindStateIMN13image_fetcher16ImageFetcherImplEFvRK4GURLRKNSt3__112basic_stringIcNS8_11char_traitsIcEENS8_9allocatorIcEEEERKNS3_15RequestMetadataEEJNS0_17UnretainedWrapperIS4_EES5_EEEFvSG_SJ_EE3RunEPNS0_13BindStateBaseESG_SJ_ + 84
	35  Chromium                            0x000000010658ccb0 _ZNKR4base8CallbackIFvRKNSt3__112basic_stringIcNS1_11char_traitsIcEENS1_9allocatorIcEEEERKN13image_fetcher15RequestMetadataEELNS_8internal8CopyModeE1ELNSF_10RepeatModeE1EE3RunES9_SD_ + 96
	36  Chromium                            0x000000010658c4a3 _ZN13image_fetcher16ImageDataFetcher13FinishRequestEPKN3net10URLFetcherERKNS_15RequestMetadataERKNSt3__112basic_stringIcNS8_11char_traitsIcEENS8_9allocatorIcEEEE + 915
	37  Chromium                            0x000000010658c0a7 _ZN13image_fetcher16ImageDataFetcher18OnURLFetchCompleteEPKN3net10URLFetcherE + 1367
	38  Chromium                            0x0000000104b1d0b9 _ZN3net14URLFetcherCore29InformDelegateFetchIsCompleteEv + 265
	39  Chromium                            0x0000000104b1cf86 _ZN3net14URLFetcherCore21OnCompletedURLRequestEN4base9TimeDeltaE + 310
	40  Chromium                            0x0000000104b228ca _ZN4base8internal13FunctorTraitsIMN3net14URLFetcherCoreEFvNS_9TimeDeltaEEvE6InvokeIRK13scoped_refptrIS3_EJRKS4_EEEvS6_OT_DpOT0_ + 154
	41  Chromium                            0x0000000104b2281f _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKMN3net14URLFetcherCoreEFvNS_9TimeDeltaEEJRK13scoped_refptrIS5_ERKS6_EEEvOT_DpOT0_ + 95
	42  Chromium                            0x0000000104b227ad _ZN4base8internal7InvokerINS0_9BindStateIMN3net14URLFetcherCoreEFvNS_9TimeDeltaEEJ13scoped_refptrIS4_ES5_EEEFvvEE7RunImplIRKS7_RKNSt3__15tupleIJS9_S5_EEEJLm0ELm1EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEE + 125
	43  Chromium                            0x0000000104b226bc _ZN4base8internal7InvokerINS0_9BindStateIMN3net14URLFetcherCoreEFvNS_9TimeDeltaEEJ13scoped_refptrIS4_ES5_EEEFvvEE3RunEPNS0_13BindStateBaseE + 44
	44  Chromium                            0x0000000101f985c1 _ZNO4base8CallbackIFvvELNS_8internal8CopyModeE0ELNS2_10RepeatModeE0EE3RunEv + 81
	45  Chromium                            0x000000010328e5a1 _ZN4base5debug13TaskAnnotator7RunTaskEPKcPNS_11PendingTaskE + 961
	46  Chromium                            0x000000010331f84e _ZN4base11MessageLoop7RunTaskEPNS_11PendingTaskE + 894
	47  Chromium                            0x000000010331fd67 _ZN4base11MessageLoop21DeferOrRunPendingTaskENS_11PendingTaskE + 71
	48  Chromium                            0x0000000103320b8a _ZN4base11MessageLoop6DoWorkEv + 650
	49  Chromium                            0x00000001035f35a1 _ZN4base24MessagePumpCFRunLoopBase7RunWorkEv + 81
	50  Chromium                            0x00000001035f353c ___ZN4base24MessagePumpCFRunLoopBase13RunWorkSourceEPv_block_invoke + 28
	51  Chromium                            0x00000001035e2631 _ZN4base3mac15CallWithEHFrameEU13block_pointerFvvE + 33
	52  Chromium                            0x00000001035f2df7 _ZN4base24MessagePumpCFRunLoopBase13RunWorkSourceEPv + 87
	53  CoreFoundation                      0x000000010ea2b761 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
	54  CoreFoundation                      0x000000010ea1098c __CFRunLoopDoSources0 + 556
	55  CoreFoundation                      0x000000010ea0fe76 __CFRunLoopRun + 918
	56  CoreFoundation                      0x000000010ea0f884 CFRunLoopRunSpecific + 420
	57  GraphicsServices                    0x00000001130faa6f GSEventRunModal + 161
	58  UIKit                               0x000000010d149c68 UIApplicationMain + 159
	59  Chromium                            0x0000000101de3e1b main + 1051
	60  libdyld.dylib                       0x00000001166a868d start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException