Revert 149966 on 1180 (M21) - Merge 147334 to 1180 (M21) - Wire the AMD switchable videcard detecti…

content/gpu/gpu_info_collector_win.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/gpu/gpu_info_collector.h"
 
 #include <windows.h>
 #include <d3d9.h>
 #include <setupapi.h>
 
@@ skipping 135 matching lines @@
   UMA_HISTOGRAM_TIMES("GPU.WinSAT.ReadResultsFileTime",
                       base::TimeTicks::Now() - start_time);
 
   return stats;
 }
 
 }  // namespace anonymous
 
 namespace gpu_info_collector {
 
-#if !defined(OFFICIAL_BUILD)
-AMDVideoCardType GetAMDVideocardType() {
-  return UNKNOWN;
-}
-#else
-// This function has a real implementation for official builds that can
-// be found in src/third_party/amd.
-AMDVideoCardType GetAMDVideocardType();
-#endif
-
 bool CollectGraphicsInfo(content::GPUInfo* gpu_info) {
   TRACE_EVENT0("gpu", "CollectGraphicsInfo");
 
   DCHECK(gpu_info);
 
   content::GpuPerformanceStats stats = RetrieveGpuPerformanceStats();
   UMA_HISTOGRAM_BOOLEAN(
       "GPU.WinSAT.HasResults",
       stats.overall != 0.0 && stats.graphics != 0.0 && stats.gaming != 0.0);
   gpu_info->performance_stats = stats;
@@ skipping 171 matching lines @@
         if (result == ERROR_SUCCESS)
           driver_date = WideToASCII(std::wstring(value));
 
         std::string driver_vendor;
         dwcb_data = sizeof(value);
         result = RegQueryValueExW(
             key, L"ProviderName", NULL, NULL,
             reinterpret_cast<LPBYTE>(value), &dwcb_data);
         if (result == ERROR_SUCCESS) {
           driver_vendor = WideToASCII(std::wstring(value));
-          if (driver_vendor == "Advanced Micro Devices, Inc." ||
-              driver_vendor == "ATI Technologies Inc.") {
-            // We are conservative and assume that in the absense of a clear
-            // signal the videocard is assumed to be switchable.
-            AMDVideoCardType amd_card_type = GetAMDVideocardType();
-            gpu_info->amd_switchable = (amd_card_type != STANDALONE);
-          }
+          // If it's an Intel GPU with a driver provided by AMD then it's
+          // probably AMD's Dynamic Switchable Graphics.
+          // TODO: detect only AMD switchable
+          gpu_info->amd_switchable =
+              driver_vendor == "Advanced Micro Devices, Inc." ||
+              driver_vendor == "ATI Technologies Inc.";
         }
 
         gpu_info->driver_vendor = driver_vendor;
         gpu_info->driver_version = driver_version;
         gpu_info->driver_date = driver_date;
         found = true;
         RegCloseKey(key);
         break;
       }
     }
@@ skipping 14 matching lines @@
 
   size_t pos = gl_version_string.find_last_not_of("0123456789.");
   if (pos != std::string::npos && pos < gl_version_string.length() - 1) {
     gpu_info->driver_version = gl_version_string.substr(pos + 1);
     return true;
   }
   return false;
 }
 
 }  // namespace gpu_info_collector