Revert "Remove impl-side-painting from about:flags"

content/browser/gpu/compositor_util.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 "content/browser/gpu/compositor_util.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 178 matching lines @@
 
   // Flags override.
   enabled |= command_line.HasSwitch(switches::kEnableDelegatedRenderer);
   enabled &= !command_line.HasSwitch(switches::kDisableDelegatedRenderer);
   return enabled;
 }
 
 bool IsImplSidePaintingEnabled() {
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
-  if (command_line.HasSwitch(switches::kDisableImplSidePainting))
+
+  if (command_line.HasSwitch(switches::kEnableImplSidePainting))
+    return true;
+  else if (command_line.HasSwitch(switches::kDisableImplSidePainting))
     return false;
+
   return true;
 }
 
 int NumberOfRendererRasterThreads() {
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
 
   int num_raster_threads = 1;
 
   // TODO(danakj): Don't do this when using async uploads. Add methods to this
@@ skipping 171 matching lines @@
     }
   }
   return problem_list;
 }
 
 std::vector<std::string> GetDriverBugWorkarounds() {
   return GpuDataManagerImpl::GetInstance()->GetDriverBugWorkarounds();
 }
 
 }  // namespace content