Disable EditDictionaryA11yTest on linux because of flaky runs.

Bug: 1012370
Change-Id: Ibd7304cc2a9c8fe81b60e26da5bbffeaa0eee324
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1857541Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Hector Carmona <hcarmona@chromium.org>
Cr-Commit-Position: refs/heads/master@{#705354}

chrome/test/data/webui/settings/a11y/edit_dictionary_a11y_test.js

@@ -5,7 +5,8 @@
 /** @fileoverview Define accessibility tests for the EDIT_DICTIONARY route.  */
 
 // Disable since the EDIT_DICTIONARY route does not exist on Mac.
-GEN('#if !defined(OS_MACOSX)');
+// TODO(crbug.com/1012370) flaky on Linux b/c assertTrue(!!languagesPage);
+GEN('#if !defined(OS_MACOSX) && !defined(OS_LINUX)');
 
 // SettingsAccessibilityTest fixture.
 GEN_INCLUDE([
@@ -103,4 +104,4 @@ AccessibilityTest.define('EditDictionaryA11yTest', {
   },
 });
 
-GEN('#endif  // !defined(OS_MACOSX)');
+GEN('#endif  // !defined(OS_MACOSX) && !defined(OS_LINUX)');