Disable WebUIMojoTest.EndToEndPing on Windows.

TBR=viettrungluu@chromium.org
BUG=418019

Review URL: https://codereview.chromium.org/609743002

Cr-Commit-Position: refs/heads/master@{#296906}

content/browser/webui/web_ui_mojo_browsertest.cc

@@ -197,7 +197,13 @@ class WebUIMojoTest : public ContentBrowserTest {
 
 // Loads a webui page that contains mojo bindings and verifies a message makes
 // it from the browser to the page and back.
-IN_PROC_BROWSER_TEST_F(WebUIMojoTest, EndToEndPing) {
+// Fails on Win only.  http://crbug.com/418019
+#if defined(OS_WIN)
+#define MAYBE_EndToEndPing DISABLED_EndToEndPing
+#else
+#define MAYBE_EndToEndPing EndToEndPing
+#endif
+IN_PROC_BROWSER_TEST_F(WebUIMojoTest, MAYBE_EndToEndPing) {
   // Currently there is no way to have a generated file included in the isolate
   // files. If the bindings file doesn't exist assume we're on such a bot and
   // pass.