Chrome 56.0.2884.0 (tip of tree)
OSX 10.11.6

What steps will reproduce the problem?
(1) Compile Chrome with DCHECKs enabled.
(2) Click on the security indicator to summon the Page Info bubble.
(3) Click  outside the bubble to dismiss it.

What is the expected output?
The bubble is dismissed safely.

What do you see instead?
Chrome freezes. It takes a minute or more to kill/Force Quit.

Stack trace:
[14747:1295:1007/181046:FATAL:bridged_native_widget.mm(540)] Check failed: !view || !compositor_widget_.
0   libbase.dylib                       0x000000011339fd53 _ZN4base5debug10StackTraceC1Ev + 19
1   libbase.dylib                       0x00000001133c5517 _ZN7logging10LogMessageD2Ev + 71
2   libviews.dylib                      0x000000011adf5fc4 _ZN5views19BridgedNativeWidget11SetRootViewEPNS_4ViewE + 132
3   libviews.dylib                      0x000000011ae7998f _ZN5views15NativeWidgetMac18ReorderNativeViewsEv + 47
4   libviews.dylib                      0x000000011ae70eb1 _ZN5views4View11CreateLayerEv + 385
5   libviews.dylib                      0x000000011ade51aa _ZThn416_N5views15InkDropHostView15AddInkDropLayerEPN2ui5LayerE + 42
6   libviews.dylib                      0x000000011ade65c5 _ZN5views11InkDropImpl26AddRootLayerToHostIfNeededEv + 197
7   libviews.dylib                      0x000000011ade6344 _ZN5views11InkDropImpl19CreateInkDropRippleEv + 228
8   libviews.dylib                      0x000000011ade6137 _ZN5views11InkDropImpl14AnimateToStateENS_12InkDropStateE + 39
9   libviews.dylib                      0x000000011ade57b8 _ZN5views15InkDropHostView17VisibilityChangedEPNS_4ViewEb + 56
10  libviews.dylib                      0x000000011ae04be4 _ZN5views12CustomButton17VisibilityChangedEPNS_4ViewEb + 20
11  libviews.dylib                      0x000000011ae70988 _ZN5views4View32PropagateVisibilityNotificationsEPS0_b + 88
12  libviews.dylib                      0x000000011ae70988 _ZN5views4View32PropagateVisibilityNotificationsEPS0_b + 88
13  libviews.dylib                      0x000000011ae70988 _ZN5views4View32PropagateVisibilityNotificationsEPS0_b + 88
14  libviews.dylib                      0x000000011ae82f02 _ZN5views6Widget31OnNativeWidgetVisibilityChangedEb + 50
15  libviews.dylib                      0x000000011adf80b1 _ZN5views19BridgedNativeWidget19OnVisibilityChangedEv + 449
16  libviews.dylib                      0x000000011adfdbd0 -[NativeWidgetMacNSWindow orderWindow:relativeTo:] + 80
17  libviews.dylib                      0x000000011ae7a1bc _ZN5views15NativeWidgetMac5CloseEv + 188
18  libviews.dylib                      0x000000011ae81c3f _ZN5views6Widget5CloseEv + 479
19  libviews.dylib                      0x000000011ae82cb7 _ZN5views6Widget31OnNativeWidgetActivationChangedEb + 391
20  libviews.dylib                      0x000000011adf84ef _ZN5views19BridgedNativeWidget26OnWindowKeyStatusChangedToEb + 47
21  CoreFoundation                      0x00007fff882c4bbc __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 12
22  CoreFoundation                      0x00007fff882c4b4f ___CFXRegistrationPost_block_invoke + 63
23  CoreFoundation                      0x00007fff882c4ac7 _CFXRegistrationPost + 407
24  CoreFoundation                      0x00007fff882c4832 ___CFXNotificationPost_block_invoke + 50
25  CoreFoundation                      0x00007fff882815e2 -[_CFXNotificationRegistrar find:object:observer:enumerator:] + 1922
26  CoreFoundation                      0x00007fff88280835 _CFXNotificationPost + 693
27  Foundation                          0x00007fff938fd17a -[NSNotificationCenter postNotificationName:object:userInfo:] + 66
28  AppKit                              0x00007fff9a94d55c -[NSWindow resignKeyWindow] + 748
29  AppKit                              0x00007fff9aac88c0 -[NSWindow _resignKeyFocus] + 92
30  AppKit                              0x00007fff9a8ca944 -[NSApplication sendEvent:] + 2296
31  libchrome_dll.dylib                 0x000000010beb83ec __34-[BrowserCrApplication sendEvent:]_block_invoke + 172
32  libbase.dylib                       0x00000001133c6c8a _ZN4base3mac15CallWithEHFrameEU13block_pointerFvvE + 10
33  libchrome_dll.dylib                 0x000000010beb8338 -[BrowserCrApplication sendEvent:] + 72
34  AppKit                              0x00007fff9a731df2 -[NSApplication run] + 796
35  libbase.dylib                       0x00000001133e0607 _ZN4base24MessagePumpNSApplication5DoRunEPNS_11MessagePump8DelegateE + 359
36  libbase.dylib                       0x00000001133df9a7 _ZN4base24MessagePumpCFRunLoopBase3RunEPNS_11MessagePump8DelegateE + 119
37  libbase.dylib                       0x00000001133db94f _ZN4base11MessageLoop10RunHandlerEv + 207
38  libbase.dylib                       0x000000011340a4c3 _ZN4base7RunLoop3RunEv + 51
39  libchrome_dll.dylib                 0x000000010bebe238 _ZN22ChromeBrowserMainParts18MainMessageLoopRunEPi + 280
40  libcontent.dylib                    0x0000000115d63944 _ZN7content15BrowserMainLoop23RunMainMessageLoopPartsEv + 52
41  libcontent.dylib                    0x0000000115d66696 _ZN7content21BrowserMainRunnerImpl3RunEv + 166
42  libcontent.dylib                    0x0000000115d5f9ac _ZN7content11BrowserMainERKNS_18MainFunctionParamsE + 124
43  libcontent.dylib                    0x00000001165c3563 _ZN7content21ContentMainRunnerImpl3RunEv + 819
44  libcontent.dylib                    0x00000001165c2536 _ZN7content11ContentMainERKNS_17ContentMainParamsE + 54
45  libchrome_dll.dylib                 0x000000010b98477c ChromeMain + 60
46  Chromium                            0x000000010b713d5a main + 522
47  Chromium                            0x000000010b713b44 start + 52


https://chromium.googlesource.com/chromium/src/+/578c39e0edd49f49d0e368eccec170c6715c3808/ui/views/cocoa/bridged_native_widget.mm#540

DCHECK triggered: https://chromium.googlesource.com/chromium/src/+/578c39e0edd49f49d0e368eccec170c6715c3808/ui/views/cocoa/bridged_native_widget.mm#540

ellyjones@, could you triage/pass on?