Revert of Remove DCHECK_IMPLIES/CHECK_IMPLIES.

gpu/command_buffer/service/texture_definition.cc

 // Copyright 2014 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 "gpu/command_buffer/service/texture_definition.h"
 
 #include <list>
 
 #include "base/lazy_instance.h"
 #include "base/memory/linked_ptr.h"
@@ skipping 316 matching lines @@
     : version_(version),
       target_(texture->target()),
       image_buffer_(image_buffer),
       min_filter_(texture->min_filter()),
       mag_filter_(texture->mag_filter()),
       wrap_s_(texture->wrap_s()),
       wrap_t_(texture->wrap_t()),
       usage_(texture->usage()),
       immutable_(texture->IsImmutable()),
       defined_(texture->IsDefined()) {
-  DCHECK(!image_buffer_.get() || defined_);
+  DCHECK_IMPLIES(image_buffer_.get(), defined_);
   if (!image_buffer_.get() && defined_) {
     image_buffer_ = NativeImageBuffer::Create(texture->service_id());
     DCHECK(image_buffer_.get());
   }
 
   const Texture::FaceInfo& first_face = texture->face_infos_[0];
   if (image_buffer_.get()) {
     scoped_refptr<gfx::GLImage> gl_image(
         new GLImageSync(image_buffer_,
                         gfx::Size(first_face.level_infos[0].width,
@@ skipping 107 matching lines @@
   return true;
 }
 
 bool TextureDefinition::SafeToRenderFrom() const {
   return level_info_.cleared_rect.Contains(
       gfx::Rect(level_info_.width, level_info_.height));
 }
 
 }  // namespace gles2
 }  // namespace gpu