Re-enable testContextMenuOpenInNewTabFromTallPage on device.

ios/chrome/browser/context_menu/context_menu_egtest.mm

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import <EarlGrey/EarlGrey.h>
 #import <UIKit/UIKit.h>
 #import <XCTest/XCTest.h>
 
 #include "base/strings/sys_string_conversions.h"
 #include "ios/chrome/browser/ui/ui_util.h"
@@ skipping 39 matching lines @@
 id<GREYMatcher> openImageInNewTabButton() {
   return buttonWithAccessibilityLabelId(
       IDS_IOS_CONTENT_CONTEXT_OPENIMAGENEWTAB);
 }
 
 // Matcher for the open link in new tab button in the context menu.
 id<GREYMatcher> openLinkInNewTabButton() {
   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,
                                     id<GREYMatcher> contextMenuItemButton) {
   [[EarlGrey selectElementWithMatcher:chrome_test_util::
                                           webViewBelongingToWebController()]
       performAction:chrome_test_util::longPressElementForContextMenu(elementId,
                                                                      true)];
 
   [[EarlGrey selectElementWithMatcher:contextMenuItemButton]
       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
 // opening a new tab through context menu, to finish before selecting tab.
 // TODO(crbug.com/643792): Remove this function when the bug is fixed.
 void SelectTabAtIndexInCurrentMode(NSUInteger index) {
   // Delay for 1 second.
   GREYCondition* myCondition = [GREYCondition conditionWithName:@"delay"
                                                           block:^BOOL {
                                                             return NO;
@@ skipping 82 matching lines @@
   // Verify url and tab count.
   [[EarlGrey selectElementWithMatcher:chrome_test_util::omniboxText(
                                           destinationURL.GetContent())]
       assertWithMatcher:grey_notNil()];
   chrome_test_util::AssertMainTabCount(2U);
 }
 
 // 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 =
       web::test::HttpServer::MakeUrl("http://scenarioContextMenuOpenInNewTab");
   GURL destinationURL = web::test::HttpServer::MakeUrl("http://destination");
 
   // The initial page contains a link to the destination page that is below a
   // really tall div so that scrolling is required.
   responses[initialURL] =
       "<div style='height:4000px'></div>"
@@ skipping 43 matching lines @@
   SelectTabAtIndexInCurrentMode(1U);
 
   // Verify url and tab count.
   [[EarlGrey selectElementWithMatcher:chrome_test_util::omniboxText(
                                           destinationURL.GetContent())]
       assertWithMatcher:grey_notNil()];
   chrome_test_util::AssertMainTabCount(2U);
 }
 
 @end