Revert of Change minimum length of Aura overlay scrollbars.

third_party/WebKit/Source/web/tests/FrameTestHelpers.h

Index: third_party/WebKit/Source/web/tests/FrameTestHelpers.h
diff --git a/third_party/WebKit/Source/web/tests/FrameTestHelpers.h b/third_party/WebKit/Source/web/tests/FrameTestHelpers.h
index 6e8ab66412334e5fa0f41c5c6c7fc74224c076cb..232875b1bbfc39e303d6ee0ee225ea6ffab7920b 100644
--- a/third_party/WebKit/Source/web/tests/FrameTestHelpers.h
+++ b/third_party/WebKit/Source/web/tests/FrameTestHelpers.h
@@ -126,15 +126,6 @@
     EXPECT_TRUE(ScrollbarTheme::theme().usesOverlayScrollbars());
   }
 
-  UseMockScrollbarSettings(bool useMock, bool useOverlay)
-      : m_originalMockScrollbarEnabled(Settings::mockScrollbarsEnabled()),
-        m_originalOverlayScrollbarsEnabled(
-            RuntimeEnabledFeatures::overlayScrollbarsEnabled()) {
-    Settings::setMockScrollbarsEnabled(useMock);
-    RuntimeEnabledFeatures::setOverlayScrollbarsEnabled(useOverlay);
-    EXPECT_EQ(useOverlay, ScrollbarTheme::theme().usesOverlayScrollbars());
-  }
-
   ~UseMockScrollbarSettings() {
     Settings::setMockScrollbarsEnabled(m_originalMockScrollbarEnabled);
     RuntimeEnabledFeatures::setOverlayScrollbarsEnabled(