cc: Add more traces to checker imaging / image hijack code paths.

cc/playback/image_hijack_canvas.cc

 // 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 "cc/playback/image_hijack_canvas.h"
 
 #include "base/optional.h"
+#include "base/trace_event/trace_event.h"
 #include "cc/playback/discardable_image_map.h"
 #include "cc/tiles/image_decode_cache.h"
 #include "third_party/skia/include/core/SkPath.h"
 
 namespace cc {
 namespace {
 
 SkIRect RoundOutRect(const SkRect& rect) {
   SkIRect result;
   rect.roundOut(&result);
@@ skipping 112 matching lines @@
                                      int height,
                                      ImageDecodeCache* image_decode_cache,
                                      const ImageIdFlatSet* images_to_skip)
     : SkNWayCanvas(width, height),
       image_decode_cache_(image_decode_cache),
       images_to_skip_(images_to_skip) {}
 
 void ImageHijackCanvas::onDrawPicture(const SkPicture* picture,
                                       const SkMatrix* matrix,
                                       const SkPaint* paint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawPicture");
   // Ensure that pictures are unpacked by this canvas, instead of being
   // forwarded to the raster canvas.
   SkCanvas::onDrawPicture(picture, matrix, paint);
 }
 
 void ImageHijackCanvas::onDrawImage(const SkImage* image,
                                     SkScalar x,
                                     SkScalar y,
                                     const SkPaint* paint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawImage");
   if (!image->isLazyGenerated()) {
     DCHECK(!ShouldSkipImage(image));
     SkNWayCanvas::onDrawImage(image, x, y, paint);
     return;
   }
 
   if (ShouldSkipImage(image))
     return;
 
   SkMatrix ctm = getTotalMatrix();
@@ skipping 18 matching lines @@
   SkNWayCanvas::onDrawImage(decoded_image.image().get(), x, y, decoded_paint);
   if (need_scale)
     SkNWayCanvas::restore();
 }
 
 void ImageHijackCanvas::onDrawImageRect(const SkImage* image,
                                         const SkRect* src,
                                         const SkRect& dst,
                                         const SkPaint* paint,
                                         SrcRectConstraint constraint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawImageRect");
   if (!image->isLazyGenerated()) {
     DCHECK(!ShouldSkipImage(image));
     SkNWayCanvas::onDrawImageRect(image, src, dst, paint, constraint);
     return;
   }
 
   if (ShouldSkipImage(image))
     return;
 
   SkRect src_storage;
@@ skipping 21 matching lines @@
     float y_scale = decoded_image.scale_adjustment().height();
     adjusted_src = SkRect::MakeXYWH(
         adjusted_src.x() * x_scale, adjusted_src.y() * y_scale,
         adjusted_src.width() * x_scale, adjusted_src.height() * y_scale);
   }
   SkNWayCanvas::onDrawImageRect(decoded_image.image().get(), &adjusted_src, dst,
                                 decoded_paint, constraint);
 }
 
 void ImageHijackCanvas::onDrawRect(const SkRect& r, const SkPaint& paint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawRect");
   if (ShouldSkipImageInPaint(paint))
     return;
 
   base::Optional<ScopedImagePaint> image_paint =
       ScopedImagePaint::TryCreate(image_decode_cache_, getTotalMatrix(), paint);
   if (!image_paint.has_value()) {
     SkNWayCanvas::onDrawRect(r, paint);
     return;
   }
   SkNWayCanvas::onDrawRect(r, image_paint.value().paint());
 }
 
 void ImageHijackCanvas::onDrawPath(const SkPath& path, const SkPaint& paint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawPath");
   if (ShouldSkipImageInPaint(paint))
     return;
 
   base::Optional<ScopedImagePaint> image_paint =
       ScopedImagePaint::TryCreate(image_decode_cache_, getTotalMatrix(), paint);
   if (!image_paint.has_value()) {
     SkNWayCanvas::onDrawPath(path, paint);
     return;
   }
   SkNWayCanvas::onDrawPath(path, image_paint.value().paint());
 }
 
 void ImageHijackCanvas::onDrawOval(const SkRect& r, const SkPaint& paint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawOval");
   if (ShouldSkipImageInPaint(paint))
     return;
 
   base::Optional<ScopedImagePaint> image_paint =
       ScopedImagePaint::TryCreate(image_decode_cache_, getTotalMatrix(), paint);
   if (!image_paint.has_value()) {
     SkNWayCanvas::onDrawOval(r, paint);
     return;
   }
   SkNWayCanvas::onDrawOval(r, image_paint.value().paint());
 }
 
 void ImageHijackCanvas::onDrawArc(const SkRect& r,
                                   SkScalar start_angle,
                                   SkScalar sweep_angle,
                                   bool use_center,
                                   const SkPaint& paint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawArc");
   if (ShouldSkipImageInPaint(paint))
     return;
 
   base::Optional<ScopedImagePaint> image_paint =
       ScopedImagePaint::TryCreate(image_decode_cache_, getTotalMatrix(), paint);
   if (!image_paint.has_value()) {
     SkNWayCanvas::onDrawArc(r, start_angle, sweep_angle, use_center, paint);
     return;
   }
   SkNWayCanvas::onDrawArc(r, start_angle, sweep_angle, use_center,
                           image_paint.value().paint());
 }
 
 void ImageHijackCanvas::onDrawRRect(const SkRRect& rr, const SkPaint& paint) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::onDrawRRect");
   if (ShouldSkipImageInPaint(paint))
     return;
 
   base::Optional<ScopedImagePaint> image_paint =
       ScopedImagePaint::TryCreate(image_decode_cache_, getTotalMatrix(), paint);
   if (!image_paint.has_value()) {
     SkNWayCanvas::onDrawRRect(rr, paint);
     return;
   }
   SkNWayCanvas::onDrawRRect(rr, image_paint.value().paint());
 }
 
 void ImageHijackCanvas::onDrawImageNine(const SkImage* image,
                                         const SkIRect& center,
                                         const SkRect& dst,
                                         const SkPaint* paint) {
   // No cc embedder issues image nine calls.
   NOTREACHED();
 }
 
 bool ImageHijackCanvas::ShouldSkipImage(const SkImage* image) const {
-  return images_to_skip_->find(image->uniqueID()) != images_to_skip_->end();
+  bool skip =
+      images_to_skip_->find(image->uniqueID()) != images_to_skip_->end();
+  TRACE_EVENT2(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
+               "ImageHijackCanvas::ShouldSkipImage", "imageId",
+               image->uniqueID(), "skip", skip);
+  return skip;
 }
 
 bool ImageHijackCanvas::ShouldSkipImageInPaint(const SkPaint& paint) const {
   const SkImage* image = GetImageInPaint(paint);
   return image ? ShouldSkipImage(image) : false;
 }
 
 }  // namespace cc