Revert of Pass initial size and GPU preference via context attributes

components/display_compositor/gl_helper_unittest.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 <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
 #include <cmath>
 #include <string>
@@ skipping 53 matching lines @@
     attributes.stencil_size = 8;
     attributes.samples = 4;
     attributes.sample_buffers = 1;
     attributes.bind_generates_resource = false;
 
     context_.reset(gpu::GLInProcessContext::Create(
         nullptr,                     /* service */
         nullptr,                     /* surface */
         true,                        /* offscreen */
         gfx::kNullAcceleratedWidget, /* window */
+        gfx::Size(1, 1),             /* size */
         nullptr,                     /* share_context */
-        attributes, gpu::SharedMemoryLimits(),
+        attributes, gl::PreferDiscreteGpu, gpu::SharedMemoryLimits(),
         nullptr, /* gpu_memory_buffer_manager */
         nullptr /* image_factory */));
     gl_ = context_->GetImplementation();
     gpu::ContextSupport* support = context_->GetImplementation();
 
     helper_.reset(new display_compositor::GLHelper(gl_, support));
     helper_scaling_.reset(
         new display_compositor::GLHelperScaling(gl_, helper_.get()));
   }
 
@@ skipping 1342 matching lines @@
     }
   }
 }
 
 TEST_F(GLHelperTest, CheckOptimizations) {
   // Test in baseclass since it is friends with GLHelperScaling
   CheckOptimizationsTest();
 }
 
 }  // namespace display_compositor