Revert "Disable MediaRouterIntegrationBrowserTest.Dialog_Basic on MacOS"

This reverts commit 075859bd.

Reason for revert: The offending patch has been reverted. I'm re-enabling this.

Original change's description:
> Disable MediaRouterIntegrationBrowserTest.Dialog_Basic on MacOS
> 
> It was detected to be flaky
> 
> TBR=mfoltz@chromium.org
> 
> Bug: 824610
> Change-Id: I958b7ecf83d01eb396638461271262599286fb7a
> Reviewed-on: https://chromium-review.googlesource.com/975304
> Reviewed-by: Christos Froussios <cfroussios@chromium.org>
> Commit-Queue: Christos Froussios <cfroussios@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#545046}

TBR=cfroussios@chromium.org

Change-Id: Ic791f98fcb60d7ed03636e3c45bcddb816f6b0bc
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 824610
Reviewed-on: https://chromium-review.googlesource.com/975441Reviewed-by: Fady Samuel <fsamuel@chromium.org>
Commit-Queue: Fady Samuel <fsamuel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545047}

chrome/test/media_router/media_router_integration_ui_browsertest.cc

@@ -12,19 +12,13 @@
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/l10n/l10n_util.h"
 
-#if defined(OS_MACOSX)
-#define MAYBE_Dialog_Basic DISABLED_Dialog_Basic
-#else
-#define MAYBE_Dialog_Basic Dialog_Basic
-#endif
-
 namespace media_router {
 
 namespace {
 const char kTestSinkName[] = "test-sink-1";
 }
 
-IN_PROC_BROWSER_TEST_F(MediaRouterIntegrationBrowserTest, MAYBE_Dialog_Basic) {
+IN_PROC_BROWSER_TEST_F(MediaRouterIntegrationBrowserTest, Dialog_Basic) {
   OpenTestPage(FILE_PATH_LITERAL("basic_test.html"));
   content::WebContents* web_contents =
       browser()->tab_strip_model()->GetActiveWebContents();