Aura overlay scrollbars shouldn't invalidate thumb on scroll or enabled state.

third_party/WebKit/Source/platform/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 import("//testing/test.gni")
 import("//third_party/WebKit/public/public_features.gni")
 import("//third_party/WebKit/Source/build/scripts/scripts.gni")
@@ skipping 1814 matching lines @@
   } else if (is_posix) {
     sources += [ "text/LocaleICUTest.cpp" ]
   }
 
   if (!is_mac) {
     sources += [ "scroll/ScrollAnimatorTest.cpp" ]
   }
 
   if (use_default_render_theme) {
     sources += [ "scroll/ScrollbarThemeAuraTest.cpp" ]
+    sources += [ "scroll/ScrollbarThemeOverlayTest.cpp" ]

[jbroman, 2016/12/22 15:21:00]

If you leave this here, put these in one list:

sources += [
  "scroll/ScrollbarThemeAuraTest.cpp",
  "scroll/ScrollbarThemeOverlayTest.cpp",
]

But ScrollbarThemeOverlay seems to be built in !use_default_render_theme builds
too, so why is this not just in the main unit test file list?

[bokan, 2016/12/22 16:10:55]

Good catch, I just put it beside the AuraTest without thinking too much. Moved
to main unittest list above.

   }
 
   sources += [ "testing/RunAllTests.cpp" ]
 
   configs += [
     ":blink_platform_pch",
     "//third_party/WebKit/Source/wtf:wtf_config",
     "//third_party/WebKit/Source:config",
   ]
 
@@ skipping 225 matching lines @@
     "//third_party/WebKit/Source:config",
     "//third_party/WebKit/Source:inside_blink",
   ]
 
   deps = [
     ":test_support",
     "//testing/gmock",
     "//testing/gtest",
   ]
 }