Re-enable testContextMenuOpenInNewTabFromTallPage on device.

ios/chrome/browser/context_menu/context_menu_egtest.mm

Index: ios/chrome/browser/context_menu/context_menu_egtest.mm
diff --git a/ios/chrome/browser/context_menu/context_menu_egtest.mm b/ios/chrome/browser/context_menu/context_menu_egtest.mm
index 65c652fda9189b8c9126a576507ee7c42cd32bf0..8f5d46c8b9e01a1cb8bc418042683b8df195851f 100644
--- a/ios/chrome/browser/context_menu/context_menu_egtest.mm
+++ b/ios/chrome/browser/context_menu/context_menu_egtest.mm
@@ -57,6 +57,20 @@
   return buttonWithAccessibilityLabelId(IDS_IOS_CONTENT_CONTEXT_OPENLINKNEWTAB);
 }
 
+// Wait until |matcher| is nil.
+void WaitForMatcherBecomesNil(id<GREYMatcher> matcher) {

[baxley, 2017/01/19 22:27:40]

Can we call it "WaitForMatcher"? I think becoming nil applies to the error
argument, rather than the matcher itself, and I think it's an implementation
detail the caller doesnt' need.

[liaoyuke, 2017/01/19 22:47:44]

Acknowledged.

+  ConditionBlock condition = ^{
+    NSError* error = nil;
+    [[EarlGrey selectElementWithMatcher:matcher] assertWithMatcher:grey_nil()
+                                                             error:&error];
+    return error == nil;
+  };
+  GREYAssert(
+      testing::WaitUntilConditionOrTimeout(testing::kWaitForUIElementTimeout,
+                                           condition),
+      [NSString stringWithFormat:@"Waiting for matcher %@ failed.", matcher]);
+}
+
 // Long press on |elementId| to trigger context menu and then tap on
 // |contextMenuItemButton| item.
 void LongPressElementAndTapOnButton(const char* elementId,
@@ -70,8 +84,10 @@ void LongPressElementAndTapOnButton(const char* elementId,
       assertWithMatcher:grey_notNil()];
   [[EarlGrey selectElementWithMatcher:contextMenuItemButton]
       performAction:grey_tap()];
-  [[EarlGrey selectElementWithMatcher:contextMenuItemButton]
-      assertWithMatcher:grey_nil()];
+
+  // Earl Grey cannot preperly synchronize with WKWebView, so adding a
+  // WaitUntilCondition to wait for the context menu to disappear.
+  WaitForMatcherBecomesNil(contextMenuItemButton);

[baxley, 2017/01/19 22:27:40]

Were you able to verify that this fixes the problem? or is it a speculative fix?

[liaoyuke, 2017/01/19 22:47:44]

Speculative. I'll keep an eye on it and once it fails again, I'll revert the CL.

 }
 
 // A simple wrapper that sleeps for 1s to wait for the animation, triggered from
@@ -174,15 +190,7 @@ - (void)testContextMenuOpenInNewTab {
 // Tests "Open in New Tab" on context menu  on a link that requires scrolling
 // on the page to verify that context menu can be properly triggered in the
 // current screen view.
-// TODO(crbug.com/681130): Re-enable this test on device.
-#if TARGET_IPHONE_SIMULATOR
-#define MAYBE_testContextMenuOpenInNewTabFromTallPage \
-  testContextMenuOpenInNewTabFromTallPage
-#else
-#define MAYBE_testContextMenuOpenInNewTabFromTallPage \
-  FLAKY_testContextMenuOpenInNewTabFromTallPage
-#endif
-- (void)MAYBE_testContextMenuOpenInNewTabFromTallPage {
+- (void)testContextMenuOpenInNewTabFromTallPage {

[baxley, 2017/01/19 22:27:40]

Did you have to modify anything to fix this method? Or is it just not flaky
anymore?

[liaoyuke, 2017/01/19 22:47:44]

Acknowledged.

   // Set up test simple http server.
   std::map<GURL, std::string> responses;
   GURL initialURL =