Remove ScrollbarTestSuite from platform/scroll

ScrollbarTestSuite registers Platform::current()->compositorSupport() to
TestingPlatformSupportWithMockScheduler, but
TestingPlatformSupportWithMockScheduler does the same thing internally.

So we can just remove ScrollbarTestSuite without any behavior change.

BUG=n/a
TEST=blink_platform_unittests

Review-Url: https://codereview.chromium.org/2621393003
Cr-Commit-Position: refs/heads/master@{#443509}

third_party/WebKit/Source/platform/scroll/ScrollableAreaTest.cpp

@@ -32,12 +32,11 @@ class ScrollbarThemeWithMockInvalidation : public ScrollbarThemeMock {
 
 }  // namespace
 
-class ScrollableAreaTest : public ScrollbarTestSuite {};
+using ScrollableAreaTest = testing::Test;
 
 TEST_F(ScrollableAreaTest, ScrollAnimatorCurrentPositionShouldBeSync) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   MockScrollableArea* scrollableArea =
       MockScrollableArea::create(ScrollOffset(0, 100));
@@ -46,9 +45,8 @@ TEST_F(ScrollableAreaTest, ScrollAnimatorCurrentPositionShouldBeSync) {
 }
 
 TEST_F(ScrollableAreaTest, ScrollbarTrackAndThumbRepaint) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   ScrollbarThemeWithMockInvalidation theme;
   MockScrollableArea* scrollableArea =
@@ -89,9 +87,8 @@ TEST_F(ScrollableAreaTest, ScrollbarTrackAndThumbRepaint) {
 }
 
 TEST_F(ScrollableAreaTest, ScrollbarGraphicsLayerInvalidation) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   ScrollbarTheme::setMockScrollbarsEnabled(true);
   MockScrollableArea* scrollableArea =
@@ -116,9 +113,8 @@ TEST_F(ScrollableAreaTest, ScrollbarGraphicsLayerInvalidation) {
 }
 
 TEST_F(ScrollableAreaTest, InvalidatesNonCompositedScrollbarsWhenThumbMoves) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   ScrollbarThemeWithMockInvalidation theme;
   MockScrollableArea* scrollableArea =
@@ -160,9 +156,8 @@ TEST_F(ScrollableAreaTest, InvalidatesNonCompositedScrollbarsWhenThumbMoves) {
 }
 
 TEST_F(ScrollableAreaTest, InvalidatesCompositedScrollbarsIfPartsNeedRepaint) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   ScrollbarThemeWithMockInvalidation theme;
   MockScrollableArea* scrollableArea =
@@ -242,9 +237,8 @@ TEST_F(ScrollableAreaTest, InvalidatesCompositedScrollbarsIfPartsNeedRepaint) {
 }
 
 TEST_F(ScrollableAreaTest, RecalculatesScrollbarOverlayIfBackgroundChanges) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   MockScrollableArea* scrollableArea =
       MockScrollableArea::create(ScrollOffset(0, 100));

third_party/WebKit/Source/platform/scroll/ScrollbarTestSuite.h

@@ -9,7 +9,6 @@
 #include "platform/scroll/ScrollableArea.h"
 #include "platform/scroll/Scrollbar.h"
 #include "platform/scroll/ScrollbarThemeMock.h"
-#include "platform/testing/TestingPlatformSupport.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "wtf/PtrUtil.h"
 #include <memory>
@@ -82,18 +81,6 @@ class MockScrollableArea : public GarbageCollectedFinalized<MockScrollableArea>,
   ScrollOffset m_maximumScrollOffset;
 };
 
-class ScrollbarTestSuite : public testing::Test {
- public:
-  ScrollbarTestSuite() {}
-
-  void SetUp() override {
-    m_config.compositorSupport = Platform::current()->compositorSupport();
-  }
-
- protected:
-  TestingPlatformSupport::Config m_config;
-};
-
 }  // namespace blink
 
 #endif

third_party/WebKit/Source/platform/scroll/ScrollbarThemeAuraTest.cpp

@@ -5,6 +5,7 @@
 #include "platform/scroll/ScrollbarThemeAura.h"
 
 #include "platform/scroll/ScrollbarTestSuite.h"
+#include "platform/testing/TestingPlatformSupport.h"
 
 namespace blink {
 
@@ -28,12 +29,11 @@ class ScrollbarThemeAuraButtonOverride final : public ScrollbarThemeAura {
 
 }  // namespace
 
-class ScrollbarThemeAuraTest : public ScrollbarTestSuite {};
+using ScrollbarThemeAuraTest = testing::Test;
 
 TEST_F(ScrollbarThemeAuraTest, ButtonSizeHorizontal) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   MockScrollableArea* mockScrollableArea = MockScrollableArea::create();
   ScrollbarThemeMock mockTheme;
@@ -57,9 +57,8 @@ TEST_F(ScrollbarThemeAuraTest, ButtonSizeHorizontal) {
 }
 
 TEST_F(ScrollbarThemeAuraTest, ButtonSizeVertical) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   MockScrollableArea* mockScrollableArea = MockScrollableArea::create();
   ScrollbarThemeMock mockTheme;
@@ -83,9 +82,8 @@ TEST_F(ScrollbarThemeAuraTest, ButtonSizeVertical) {
 }
 
 TEST_F(ScrollbarThemeAuraTest, NoButtonsReturnsSize0) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   MockScrollableArea* mockScrollableArea = MockScrollableArea::create();
   ScrollbarThemeMock mockTheme;

third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlayTest.cpp

@@ -5,18 +5,18 @@
 #include "platform/scroll/ScrollbarThemeOverlay.h"
 
 #include "platform/scroll/ScrollbarTestSuite.h"
+#include "platform/testing/TestingPlatformSupport.h"
 
 namespace blink {
 
 using testing::NiceMock;
 using testing::Return;
 
-class ScrollbarThemeOverlayTest : public ScrollbarTestSuite {};
+using ScrollbarThemeOverlayTest = testing::Test;
 
 TEST_F(ScrollbarThemeOverlayTest, PaintInvalidation) {
-  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler,
-                               const TestingPlatformSupport::Config&>
-      platform(m_config);
+  ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
+      platform;
 
   NiceMock<MockScrollableArea>* mockScrollableArea =
       new NiceMock<MockScrollableArea>(ScrollOffset(100, 100));