Re-enable modal dialog in iframe tests.

They were flaky a while ago, but the underlying flakiness should
be fixed now. Also add cross-platform "blink" expectations, which
will making catching flakiness even easier with more coverage.

BUG=622387

Review-Url: https://codereview.chromium.org/2892773002
Cr-Commit-Position: refs/heads/master@{#473452}

content/browser/accessibility/dump_accessibility_tree_browsertest.cc

@@ -1297,22 +1297,13 @@ IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest,
   RunHtmlTest(FILE_PATH_LITERAL("modal-dialog-opened.html"));
 }
 
-// Flaky: crbug.com/593846, crbug.com/596514
 IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest,
-                       DISABLED_AccessibilityModalDialogInIframeClosed) {
+                       AccessibilityModalDialogInIframeClosed) {
   RunHtmlTest(FILE_PATH_LITERAL("modal-dialog-in-iframe-closed.html"));
 }
 
-// Flaky on Windows and Mac: crbug.com/593846
-#if defined(OS_WIN) || defined(OS_MACOSX)
-#define MAYBE_AccessibilityModalDialogInIframeOpened \
-    DISABLED_AccessibilityModalDialogInIframeOpened
-#else
-#define MAYBE_AccessibilityModalDialogInIframeOpened \
-    AccessibilityModalDialogInIframeOpened
-#endif
 IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest,
-                       MAYBE_AccessibilityModalDialogInIframeOpened) {
+                       AccessibilityModalDialogInIframeOpened) {
   RunHtmlTest(FILE_PATH_LITERAL("modal-dialog-in-iframe-opened.html"));
 }
 

content/test/data/accessibility/html/modal-dialog-in-iframe-closed-expected-android.txt

 android.webkit.WebView focusable focused scrollable
 ++android.view.View
-++++android.view.View clickable name='Test for modal dialog closed in an iframe. '
+++++android.view.View name='Test for modal dialog closed in an iframe. '
 ++++android.view.View
-++++++android.view.View focusable scrollable
+++++++android.view.View scrollable
 ++++++++android.view.View
 ++++++++++android.widget.Button role_description='button' clickable focusable name='I am a non-inert button!'

content/test/data/accessibility/html/modal-dialog-in-iframe-closed-expected-blink.txt

+rootWebArea
+++genericContainer
+++++staticText name='Test for modal dialog closed in an iframe. '
+++++++inlineTextBox name='Test for modal dialog closed in an iframe. '
+++++iframe
+++++++rootWebArea
+++++++++genericContainer
+++++++++++button name='I am a non-inert button!'

content/test/data/accessibility/html/modal-dialog-in-iframe-opened-expected-blink.txt

+rootWebArea
+++genericContainer
+++++staticText name='Test for modal dialog opened in an iframe. '
+++++++inlineTextBox name='Test for modal dialog opened in an iframe. '
+++++iframe
+++++++rootWebArea
+++++++++dialog
+++++++++++staticText name='Text in the dialog.'
+++++++++++++inlineTextBox name='Text in the dialog.'