cc: Move canvas clear from picture to picture_pile_impl

This moves a clear per picture into a clear-to-background color
per picture pile. We need this to ensure that a solid color
page in low res is considered solid, since all the draws are
of the same color.

BUG=233622

Review URL: https://chromiumcodereview.appspot.com/14322017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198272 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 14 insertions, 2 deletions

diff --git a/skia/ext/analysis_canvas.cc b/skia/ext/analysis_canvas.cc
index 321ee2b..196d1d0 100644
--- a/skia/ext/analysis_canvas.cc
+++ b/skia/ext/analysis_canvas.cc
@@ -173,7 +173,8 @@ void AnalysisDevice::clear(SkColor color) {
 
 void AnalysisDevice::drawPaint(const SkDraw&, const SkPaint& paint) {
   addBitmapFromPaint(paint);
-  isSolidColor_ = false;
+  isSolidColor_ =
+      (isSolidColor_ && isSolidColorPaint(paint) && paint.getColor() == color_);
   isTransparent_ = false;
 }
 
@@ -221,9 +222,12 @@ void AnalysisDevice::drawRect(const SkDraw& draw, const SkRect& rect,
   // - We're not in "forced not solid" mode
   // - Paint is solid color
   // - The quad is a full tile quad
+  //    - The exception is if the tile is already solid tile,
+  //      and we're drawing the same solid color paint then
+  //      the tile remains solid.
   if (!isForcedNotSolid_ &&
       isSolidColorPaint(paint) &&
-      doesCoverCanvas) {
+      (doesCoverCanvas || (isSolidColor_ && paint.getColor() == color_))) {
     isSolidColor_ = true;
     color_ = paint.getColor();
     hasText_ = false;
diff --git a/skia/ext/analysis_canvas_unittest.cc b/skia/ext/analysis_canvas_unittest.cc
index 3cc2553..aa69259 100644
--- a/skia/ext/analysis_canvas_unittest.cc
+++ b/skia/ext/analysis_canvas_unittest.cc
@@ -223,9 +223,17 @@ TEST(AnalysisCanvasTest, SimpleDrawRect) {
   EXPECT_NE(static_cast<SkColor>(SK_ColorTRANSPARENT), outputColor);
   EXPECT_EQ(color, outputColor);
 
+  // Paint with the same color, tile should remain solid.
   canvas.rotate(50);
   canvas.drawRect(SkRect::MakeWH(255, 255), paint);
 
+  EXPECT_TRUE(canvas.getColorIfSolid(&outputColor));
+  EXPECT_EQ(color, outputColor);
+
+  color = SkColorSetARGB(255, 12, 23, 34);
+  paint.setColor(color);
+  paint.setXfermodeMode(SkXfermode::kSrcOver_Mode);
+  canvas.drawRect(SkRect::MakeWH(255, 255), paint);
   EXPECT_FALSE(canvas.getColorIfSolid(&outputColor));
 }