image: Remove operator for converting from SkBitmap to ImageSkia.

ui/gfx/image/image_skia.cc

 // Copyright (c) 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 "ui/gfx/image/image_skia.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 
@@ skipping 142 matching lines @@
 }
 
 ImageSkia::ImageSkia(const ImageSkia& other) : storage_(other.storage_) {
 }
 
 ImageSkia& ImageSkia::operator=(const ImageSkia& other) {
   storage_ = other.storage_;
   return *this;
 }
 
-ImageSkia& ImageSkia::operator=(const SkBitmap& other) {
-  Init(ImageSkiaRep(other, ui::SCALE_FACTOR_100P));
-  return *this;
-}
-
 ImageSkia::~ImageSkia() {
 }
 
 bool ImageSkia::BackedBySameObjectAs(const gfx::ImageSkia& other) const {
   return storage_.get() == other.storage_.get();
 }
 
 void ImageSkia::AddRepresentation(const ImageSkiaRep& image_rep) {
   DCHECK(!image_rep.is_null());
 
@@ skipping 107 matching lines @@
   }
 
   ImageSkiaReps::iterator it =
       storage_->FindRepresentation(ui::SCALE_FACTOR_100P, true);
   if (it != storage_->image_reps().end())
     return it->mutable_sk_bitmap();
   return NullImageRep().mutable_sk_bitmap();
 }
 
 }  // namespace gfx