Split paint property update tests out of PaintPropertyTreeBuilderTest

PaintPropertyTreeBuilderTest is over 3.5k lines long which is becoming
unwieldy. This patch splits out the incremental update tests.

BUG=645667
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2589003002
Cr-Commit-Position: refs/heads/master@{#439712}

third_party/WebKit/Source/core/BUILD.gn

@@ -1265,7 +1265,9 @@ source_set("unit_tests") {
     "paint/PaintLayerScrollableAreaTest.cpp",
     "paint/PaintLayerTest.cpp",
     "paint/PaintPropertyTreeBuilderTest.cpp",
+    "paint/PaintPropertyTreeBuilderTest.h",
     "paint/PaintPropertyTreePrinterTest.cpp",
+    "paint/PaintPropertyTreeUpdateTests.cpp",
     "paint/PrePaintTreeWalkTest.cpp",
     "paint/SVGInlineTextBoxPainterTest.cpp",
     "paint/StubChromeClientForSPv2.h",

third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilderTest.h

+// Copyright 2016 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.
+
+#include "core/layout/LayoutTestHelper.h"
+#include "platform/testing/RuntimeEnabledFeaturesTestHelpers.h"
+#include "platform/testing/UnitTestHelpers.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+class TransformPaintPropertyNode;
+class ClipPaintPropertyNode;
+class ScrollPaintPropertyNode;
+class LayoutPoint;
+
+typedef bool TestParamRootLayerScrolling;
+class PaintPropertyTreeBuilderTest
+    : public ::testing::WithParamInterface<TestParamRootLayerScrolling>,
+      private ScopedSlimmingPaintV2ForTest,
+      private ScopedRootLayerScrollingForTest,
+      public RenderingTest {
+ public:
+  PaintPropertyTreeBuilderTest()
+      : ScopedSlimmingPaintV2ForTest(true),
+        ScopedRootLayerScrollingForTest(GetParam()),
+        RenderingTest(SingleChildFrameLoaderClient::create()) {}
+
+ protected:
+  void loadTestData(const char* fileName);
+
+  // The following helpers return paint property nodes associated with the main
+  // FrameView, accounting for differences from the RootLayerScrolls setting.
+  const TransformPaintPropertyNode* framePreTranslation();
+  const TransformPaintPropertyNode* frameScrollTranslation();
+  const ClipPaintPropertyNode* frameContentClip();
+  const ScrollPaintPropertyNode* frameScroll(FrameView* = nullptr);
+
+  // Return the local border box's paint offset. For more details, see
+  // ObjectPaintProperties::localBorderBoxProperties().
+  LayoutPoint paintOffset(const LayoutObject*);
+
+ private:
+  void SetUp() override;
+  void TearDown() override;
+};
+
+}  // namespace blink