cc::SharedQuadState: drop CopyFrom and add copy constructor

cc/quads/shared_quad_state.cc

 // Copyright 2012 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/quads/shared_quad_state.h"
 
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "base/values.h"
 #include "cc/base/math_util.h"
 #include "cc/debug/traced_value.h"
 
 namespace cc {
 
 SharedQuadState::SharedQuadState()
     : is_clipped(false),
       opacity(0.f),
       blend_mode(SkXfermode::kSrcOver_Mode),
       sorting_context_id(0) {
 }
 
+SharedQuadState::SharedQuadState(const SharedQuadState& other) = default;
+
 SharedQuadState::~SharedQuadState() {
   TRACE_EVENT_OBJECT_DELETED_WITH_ID(
       TRACE_DISABLED_BY_DEFAULT("cc.debug.quads"),
       "cc::SharedQuadState", this);
 }
 
-void SharedQuadState::CopyFrom(const SharedQuadState* other) {
-  *this = *other;
-}
-
 void SharedQuadState::SetAll(const gfx::Transform& quad_to_target_transform,
                              const gfx::Size& quad_layer_bounds,
                              const gfx::Rect& visible_quad_layer_rect,
                              const gfx::Rect& clip_rect,
                              bool is_clipped,
                              float opacity,
                              SkXfermode::Mode blend_mode,
                              int sorting_context_id) {
   this->quad_to_target_transform = quad_to_target_transform;
   this->quad_layer_bounds = quad_layer_bounds;
@@ skipping 18 matching lines @@
   value->SetDouble("opacity", opacity);
   value->SetString("blend_mode", SkXfermode::ModeName(blend_mode));
   TracedValue::MakeDictIntoImplicitSnapshotWithCategory(
       TRACE_DISABLED_BY_DEFAULT("cc.debug.quads"),
       value,
       "cc::SharedQuadState",
       this);
 }
 
 }  // namespace cc