Make DragControllerTest use RenderingTest

DragControllerTest is complex and duplicates logic in RenderingTest. This patch
switches the test to use RenderingTest. This lets us remove redundant logic,
remove unused variables such as performance_, and will make it possible to
create iframe tests in the future (which require SingleChildLocalFrameClient).

This is just a cleanup and should have no change in behavior.

Bug: 766355
Change-Id: I313a9cc4a33aa1afdba5f89be52630762930b3ae
Reviewed-on: https://chromium-review.googlesource.com/671164
Commit-Queue: Philip Rogers <pdr@chromium.org>
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#503630}

third_party/WebKit/Source/core/page/DragControllerTest.cpp

@@ -8,56 +8,32 @@
 #include "core/editing/FrameSelection.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/LocalFrameView.h"
-#include "core/frame/PerformanceMonitor.h"
 #include "core/frame/VisualViewport.h"
-#include "core/html/HTMLElement.h"
-#include "core/layout/LayoutObject.h"
-#include "core/layout/LayoutView.h"
+#include "core/layout/LayoutTestHelper.h"
 #include "core/page/AutoscrollController.h"
 #include "core/page/DragData.h"
 #include "core/page/DragSession.h"
-#include "core/testing/DummyPageHolder.h"
 #include "core/testing/sim/SimDisplayItemList.h"
 #include "core/testing/sim/SimRequest.h"
 #include "core/testing/sim/SimTest.h"
-#include "core/timing/Performance.h"
 #include "platform/DragImage.h"
 #include "platform/testing/RuntimeEnabledFeaturesTestHelpers.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
-class DragControllerTest : public ::testing::Test {
+class DragControllerTest : public RenderingTest {
  protected:
-  DragControllerTest() = default;
-  ~DragControllerTest() override = default;
-
-  Document& GetDocument() const { return dummy_page_holder_->GetDocument(); }
+  DragControllerTest() : RenderingTest(SingleChildLocalFrameClient::Create()) {}
   LocalFrame& GetFrame() const { return *GetDocument().GetFrame(); }
-  Performance* GetPerformance() const { return performance_; }
-
-  void SetBodyContent(const std::string& body_content) {
-    GetDocument().body()->SetInnerHTMLFromString(
-        String::FromUTF8(body_content.c_str()));
-    UpdateAllLifecyclePhases();
-  }
 
   void UpdateAllLifecyclePhases() {
     GetDocument().View()->UpdateAllLifecyclePhases();
   }
-
- private:
-  void SetUp() override {
-    dummy_page_holder_ = DummyPageHolder::Create(IntSize(800, 600));
-    performance_ = Performance::Create(GetDocument().domWindow());
-  }
-
-  std::unique_ptr<DummyPageHolder> dummy_page_holder_;
-  Persistent<Performance> performance_;
 };
 
-TEST_F(DragControllerTest, dragImageForSelectionUsesPageScaleFactor) {
-  SetBodyContent(
+TEST_F(DragControllerTest, DragImageForSelectionUsesPageScaleFactor) {
+  SetBodyInnerHTML(
       "<div>Hello world! This tests that the bitmap for drag image is scaled "
       "by page scale factor</div>");
   GetFrame().GetPage()->GetVisualViewport().SetScale(1);
@@ -127,7 +103,7 @@ TEST_P(DragControllerSimTest, DropURLOnNonNavigatingClearsState) {
 }
 
 TEST_F(DragControllerTest, DragImageForSelectionClipsToViewport) {
-  SetBodyContent(
+  SetBodyInnerHTML(
       "<style>"
       "  * { margin: 0; } "
       "  html, body { height: 2000px; }"