Mark, assigning to you as I think you wrote this test. Please reassign if you are not a test author.

Eugene, Could you paste in some of the details about the failure? Something like an excerpt from the log showing where it failed. The link is good but is typically gone within a week.

ContextMenuTestCase.testContextMenuOpenInNewTabFromTallPage: 
2017-01-13 06:35:02.444 ios_chrome_integration_egtests[73740:8154665] Adjusting repeatCount to 8.375000 for animation <CAKeyframeAnimation: 0x156316b00>
2017-01-13 06:35:02.452 ios_chrome_integration_egtests[73740:8154665] Adjusting repeatCount to 8.375000 for animation <CAKeyframeAnimation: 0x1560d5ba0>
2017-01-13 06:35:02.689 ios_chrome_integration_egtests[73740:8154665] View is moving to nil window. Skipping viewWillDisappear state tracking.
2017-01-13 06:35:03.191 ios_chrome_integration_egtests[73740:8154665] Adjusting repeatCount to 8.375000 for animation <CAKeyframeAnimation: 0x156310950>
2017-01-13 06:35:03.413 ios_chrome_integration_egtests[73740:8154665] Adjusting repeatCount to 8.375000 for animation <CAKeyframeAnimation: 0x156074670>
../../ios/chrome/browser/context_menu/context_menu_egtest.mm:73: error: -[ContextMenuTestCase testContextMenuOpenInNewTabFromTallPage] : Assertion 'assertWithMatcher:nil' failed.
(
	0   EarlGrey                            0x0000000103ab5b50 -[XCTestCase(GREYAdditions) grey_markAsFailedAtLine:inFile:reason:detailDescription:] + 112
	1   EarlGrey                            0x0000000103ac7178 -[GREYDefaultFailureHandler handleException:details:] + 1672
	2   EarlGrey                            0x0000000103ac1d80 -[GREYElementInteraction grey_handleFailureOfAssertion:assertionError:elementNotFoundError:userProvidedOutError:] + 1308
	3   EarlGrey                            0x0000000103ac0fd8 __39-[GREYElementInteraction assert:error:]_block_invoke + 796
	4   EarlGrey                            0x0000000103ad520c __59-[GREYUIThreadExecutor executeSyncWithTimeout:block:error:]_block_invoke + 40
	5   EarlGrey                            0x0000000103ad389c __54-[GREYRunLoopSpinner grey_checkConditionInActiveMode:]_block_invoke + 252
	6   CoreFoundation                      0x0000000182468f84 <redacted> + 20
	7   CoreFoundation                      0x00000001824688bc <redacted> + 308
	8   CoreFoundation                      0x0000000182466820 <redacted> + 708
	9   CoreFoundation                      0x0000000182390c50 CFRunLoopRunSpecific + 384
	10  EarlGrey                            0x0000000103ad3708 -[GREYRunLoopSpinner grey_checkConditionInActiveMode:] + 252
	11  EarlGrey                            0x0000000103ad2bec -[GREYRunLoopSpinner spinWithStopConditionBlock:] + 520
	12  EarlGrey                            0x0000000103ad50e0 -[GREYUIThreadExecutor executeSyncWithTimeout:block:error:] + 764
	13  EarlGrey                            0x0000000103ac0a3c -[GREYElementInteraction assert:error:] + 932
	14  EarlGrey                            0x0000000103ac1128 -[GREYElementInteraction assertWithMatcher:] + 68
	15  ios_chrome_integration_egtests      0x000000010070acac _ZN12_GLOBAL__N_130LongPressElementAndTapOnButtonEPKcPU22objcproto11GREYMatcher11objc_object + 556
	16  ios_chrome_integration_egtests      0x000000010070b714 -[ContextMenuTestCase testContextMenuOpenInNewTabFromTallPage] + 880
	17  CoreFoundation                      0x00000001824b8a60 <redacted> + 144
	18  CoreFoundation                      0x00000001823b0488 <redacted> + 284
	19  XCTest                              0x00000001039b634c __24-[XCTestCase invokeTest]_block_invoke_2 + 388
	20  XCTest                              0x00000001039eae9c -[XCTestContext performInScope:] + 208
	21  XCTest                              0x00000001039b61b0 -[XCTestCase invokeTest] + 268
	22  EarlGrey                            0x0000000103ab60e8 -[XCTestCase(GREYAdditions) grey_invokeTest] + 992
	23  XCTest                              0x00000001039b6884 -[XCTestCase performTest:] + 460
	24  XCTest                              0x00000001039b3d00 -[XCTestSuite performTest:] + 428
	25  XCTest                              0x00000001039b3d00 -[XCTestSuite performTest:] + 428
	26  XCTest                              0x00000001039b3d00 -[XCTestSuite performTest:] + 428
	27  XCTest                              0x000000010399fc74 __25-[XCTestDriver _runSuite]_block_invoke + 56
	28  XCTest                              0x00000001039c0504 -[XCTestObservationCenter _observeTestExecutionForBlock:] + 528
	29  XCTest                              0x000000010399fb0c -[XCTestDriver _runSuite] + 460
	30  XCTest                              0x00000001039a0890 -[XCTestDriver _checkForTestManager] + 296
	31  XCTest                              0x00000001039ec368 _XCTestMain + 628
	32  CoreFoundation                      0x0000000182468f84 <redacted> + 20
	33  CoreFoundation                      0x00000001824688bc <redacted> + 308
	34  CoreFoundation                      0x0000000182466820 <redacted> + 708
	35  CoreFoundation                      0x0000000182390c50 CFRunLoopRunSpecific + 384
	36  GraphicsServices                    0x0000000183c78088 GSEventRunModal + 180
	37  UIKit                               0x0000000187672088 UIApplicationMain + 204
	38  ios_chrome_integration_egtests      0x00000001000f6d10 main + 576
	39  libdyld.dylib                       0x0000000181f2e8b8 <redacted> + 4
)

Exception: AssertionFailedException
Reason: Assertion 'assertWithMatcher:nil' failed.
Element matcher: (((respondsToSelector(isAccessibilityElement) && isAccessibilityElement) && accessibilityLabel("Open in New Tab")) && ((respondsToSelector(isAccessibilityElement) && isAccessibilityElement) && accessibilityTraits: UIAccessibilityTraitButton))
Complete Error: Error Domain=com.google.earlgrey.ElementInteractionErrorDomain Code=2 "UI element '<_UIAlertControllerActionView: 0x15608d5f0; frame = (0 0; 300 57); Action = <UIAlertAction: 0x1560a8a80 Title = "Open in New Tab" Descriptive = "(null)" Image = 0x0>>' failed to match nil" UserInfo={NSLocalizedDescription=UI element '<_UIAlertControllerActionView: 0x15608d5f0; frame = (0 0; 300 57); Action = <UIAlertAction: 0x1560a8a80 Title = "Open in New Tab" Descriptive = "(null)" Image = 0x0>>' failed to match nil}

Screenshot At Failure: /var/mobile/Containers/Data/Application/B92B4EC7-1557-41C7-AFA2-70B235B5340C/Documents/ContextMenuTestCase_testContextMenuOpenInNewTabFromTallPage.png
Visibility Checker's Most Recent Before Image: /var/mobile/Containers/Data/Application/B92B4EC7-1557-41C7-AFA2-70B235B5340C/Documents/ContextMenuTestCase_testContextMenuOpenInNewTabFromTallPage_before.png
Visibility Checker's Most Recent Expected After Image: /var/mobile/Containers/Data/Application/B92B4EC7-1557-41C7-AFA2-70B235B5340C/Documents/ContextMenuTestCase_testContextMenuOpenInNewTabFromTallPage_after_expected.png
Visibility Checker's Most Recent Actual After Image: /var/mobile/Containers/Data/Application/B92B4EC7-1557-41C7-AFA2-70B235B5340C/Documents/ContextMenuTestCase_testContextMenuOpenInNewTabFromTallPage_after_actual.png

Screenshot from the bot

Deleted: ContextMenuTestCase_testContextMenuOpenInNewTabFromTallPage.png 316 KB

	ContextMenuTestCase_testContextMenuOpenInNewTabFromTallPage.png 316 KB View Download

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9f47425664522cc66295d3e5837e3ad07acd6241

commit 9f47425664522cc66295d3e5837e3ad07acd6241
Author: eugenebut <eugenebut@chromium.org>
Date: Fri Jan 13 22:52:56 2017

Marked testContextMenuOpenInNewTabFromTallPage flaky on device.

BUG= 681130 

Review-Url: https://codereview.chromium.org/2632783002
Cr-Commit-Position: refs/heads/master@{#443708}

[modify] https://crrev.com/9f47425664522cc66295d3e5837e3ad07acd6241/ios/chrome/browser/context_menu/context_menu_egtest.mm

Is this now fixed?

This isn't fixed, sorry. I wrote the basic context menu egtests, but I didn't write this test case; bouncing to liaoyuke@.

[Auto-generated comment by a script] We noticed that this issue is targeted for M-57; it appears the fix may have landed after branch point, meaning a merge might be required. Please confirm if a merge is required here - if so add Merge-Request-57 label, otherwise remove Merge-TBD label. Thanks.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9b083d4867c993630dc831989ce9928eb3b8bc5f

commit 9b083d4867c993630dc831989ce9928eb3b8bc5f
Author: msarda <msarda@chromium.org>
Date: Thu Mar 02 09:37:39 2017

Re-enable testSignInSwitchAccountsAndImportData on devices.

The test testSignInSwitchAccountsAndImportData is now passing on the
flaky bots:
* https://uberchromegw.corp.google.com/i/internal.bling.fyi/builders/flaky-device/builds/16164/steps/ios_chrome_flaky_egtests%20%28iPhone%206s%20iOS%2010.0.1%29%20on%20iOS-10.0.1/logs/stdio
* https://uberchromegw.corp.google.com/i/internal.bling.fyi/builders/flaky-device/builds/16162/steps/ios_chrome_flaky_egtests%20%28iPhone%205s%20iOS%209.3.2%29%20on%20iOS-9.3.2/logs/stdio
* https://uberchromegw.corp.google.com/i/internal.bling.fyi/builders/flaky-device/builds/16161/steps/ios_chrome_flaky_egtests%20%28iPhone%205s%20iOS%209.3.2%29%20on%20iOS-9.3.2/logs/stdio

This CL re-enables it.

BUG= 681130 

Review-Url: https://codereview.chromium.org/2715403003
Cr-Commit-Position: refs/heads/master@{#454219}

[modify] https://crrev.com/9b083d4867c993630dc831989ce9928eb3b8bc5f/ios/chrome/browser/ui/authentication/signin_interaction_controller_egtest.mm