fix flaky compilation of chrome browser test_support_ui

web_ui_test_handler.cc includes auto-generated web_ui_tester.mojom.h for
non-android builds, but test_support_ui does not have a dependency from
//chrome/common:mojo_bindinds, so, compilation sometimes fails.


Bug: 
Change-Id: Ide7d3255a9156e2c70ae13d25ef3946435d3af7a
Reviewed-on: https://chromium-review.googlesource.com/652247
Reviewed-by: Bernhard Bauer <[email protected]>
Commit-Queue: Bernhard Bauer <[email protected]>
Cr-Commit-Position: refs/heads/master@{#499959}
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index f24cfb8..f22b101 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -4660,6 +4660,8 @@
       "ui/webui/web_ui_test_handler.cc",
       "ui/webui/web_ui_test_handler.h",
     ]
+
+    deps += [ "//chrome/common:mojo_bindings" ]
   }
 
   configs += [ "//build/config:precompiled_headers" ]