Move all fast-path paint invalidation mapping into PaintInvalidationState

- Remove the optional const PaintInvalidationState* parameter from paint
  invalidation mapping methods and move fast-path mapping code into
  PaintInvalidationState.

- PaintLayer::computePaintInvalidationRect() is now
    PaintInvalidationState::computePaintInvalidationRectInBacking();
  PaintLayer::positionFromPaintInvalidationBacking() is now
    PaintInvalidationState::positionFromPaintInvalidationBacking();
  PaintLayer::mapRectToPaintInvalidationBacking() is now
    PaintInvalidationState::mapLocalRectToPaintInvalidationBacking().

- Change LayoutObject::clippedOverflowRectForPaintInvalidationBacking() to:
  * Non-SVG objects and LayoutSVGRoot:
    LayoutObject::localOverflowRectForPaintInvalidation() which doesn't
    map the rect to paint invalidation backing;
  * SVG objects except LayoutSVGRoot:
    Using existing paintInvalidationRectInLocalSVGCoordinates()

  PaintInvalidationState::computePaintInvalidationRectInBacking(),
  calls the above functions to get the local paint invalidation rect,
  and map to paintInvalidationContainer using fast path if possible,
  or slow path by calling LayoutObject::mapToVisibleRectToAncestor().

- Let selection paint invalidation go through fast-path if possible.

BUG=591199

Review URL: https://codereview.chromium.org/1813383002

Cr-Commit-Position: refs/heads/master@{#383430}

1 files changed, 5 insertions, 3 deletions

diff --git a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
index af2bed6..e5294b7 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
@@ -360,12 +360,12 @@ void LayoutBoxModelObject::invalidateTreeIfNeeded(const PaintInvalidationState&
 {
     ASSERT(!needsLayout());
 
-    if (!shouldCheckForPaintInvalidation(paintInvalidationState))
+    PaintInvalidationState newPaintInvalidationState(paintInvalidationState, *this);
+    if (!shouldCheckForPaintInvalidation(newPaintInvalidationState))
         return;
 
     LayoutRect previousPaintInvalidationRect = this->previousPaintInvalidationRect();
 
-    PaintInvalidationState newPaintInvalidationState(paintInvalidationState, *this);
     // TODO(wangxianzhu): Enable this assert after we fix all paintInvalidationContainer mismatch issues. crbug.com/360286
     // ASSERT(&newPaintInvalidationState.paintInvalidationContainer() == &containerForPaintInvalidation());
 
@@ -378,6 +378,8 @@ void LayoutBoxModelObject::invalidateTreeIfNeeded(const PaintInvalidationState&
     if (reason == PaintInvalidationLocationChange)
         newPaintInvalidationState.setForceSubtreeInvalidationWithinContainer();
 
+    // TODO(wangxianzhu): Combine this function into LayoutObject::invalidateTreeIfNeeded() when removing the following workarounds.
+
     // TODO(wangxianzhu): This is a workaround for crbug.com/533277. Will remove when we enable paint offset caching.
     if (reason != PaintInvalidationNone && hasPercentageTransform(styleRef()))
         newPaintInvalidationState.setForceSubtreeInvalidationWithinContainer();
@@ -390,7 +392,7 @@ void LayoutBoxModelObject::invalidateTreeIfNeeded(const PaintInvalidationState&
         && hasOverflowClip())
         newPaintInvalidationState.setForceSubtreeInvalidationRectUpdateWithinContainer();
 
-    newPaintInvalidationState.updatePaintOffsetAndClipForChildren();
+    newPaintInvalidationState.updateForChildren();
     invalidatePaintOfSubtreesIfNeeded(newPaintInvalidationState);
 }