Add support for converting cc::Region to and from protobuf.

cc/playback/clip_path_display_item.cc

 // Copyright 2015 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/clip_path_display_item.h"
 
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "cc/proto/display_item.pb.h"
 #include "cc/proto/skia_conversions.h"
@@ skipping 23 matching lines @@
 void ClipPathDisplayItem::ToProtobuf(proto::DisplayItem* proto) const {
   proto->set_type(proto::DisplayItem::Type_ClipPath);
 
   proto::ClipPathDisplayItem* details = proto->mutable_clip_path_item();
   details->set_clip_op(SkRegionOpToProto(clip_op_));
   details->set_antialias(antialias_);
 
   // Just use skia's serialization method for the SkPath for now.
   size_t path_size = clip_path_.writeToMemory(nullptr);
   if (path_size > 0) {
-    scoped_ptr<char[]> buffer(new char[path_size]);
+    scoped_ptr<uint8_t> buffer(new uint8_t[path_size]);
     clip_path_.writeToMemory(buffer.get());
-    details->set_clip_path(std::string(buffer.get(), path_size));
+    details->set_clip_path(buffer.get(), path_size);

[David Trainor- moved to gerrit, 2015/11/20 21:46:50]

base::checked_cast<int>?

   }
 }
 
 void ClipPathDisplayItem::FromProtobuf(const proto::DisplayItem& proto) {
   DCHECK_EQ(proto::DisplayItem::Type_ClipPath, proto.type());
 
   const proto::ClipPathDisplayItem& details = proto.clip_path_item();
   SkRegion::Op clip_op = SkRegionOpFromProto(details.clip_op());
   bool antialias = details.antialias();
 
   SkPath clip_path;
   if (details.has_clip_path()) {
-    size_t bytes_read = clip_path.readFromMemory(details.clip_path().c_str(),
+    size_t bytes_read = clip_path.readFromMemory(details.clip_path().data(),
                                                  details.clip_path().size());
     DCHECK_EQ(details.clip_path().size(), bytes_read);
   }
 
   SetNew(clip_path, clip_op, antialias);
 }
 
 void ClipPathDisplayItem::Raster(SkCanvas* canvas,
                                  const gfx::Rect& canvas_target_playback_rect,
                                  SkPicture::AbortCallback* callback) const {
@@ skipping 29 matching lines @@
     SkPicture::AbortCallback* callback) const {
   canvas->restore();
 }
 
 void EndClipPathDisplayItem::AsValueInto(
     base::trace_event::TracedValue* array) const {
   array->AppendString("EndClipPathDisplayItem");
 }
 
 }  // namespace cc