Do not lose secondary gpus and make sure to have an active gpu on multiple gpu configurations

gpu/config/gpu_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 "gpu/config/gpu_util.h"
 
 #include <memory>
 #include <vector>
 
 #include "base/command_line.h"
@@ skipping 28 matching lines @@
   for (const base::StringPiece& piece :
        base::SplitStringPiece(str, ",", base::TRIM_WHITESPACE,
                               base::SPLIT_WANT_ALL)) {
     int number = 0;
     bool succeed = base::StringToInt(piece, &number);
     DCHECK(succeed);
     list->insert(number);
   }
 }
 
+// |str| is in the format of "0x040a;0x10de;...;hex32_N".
+void StringToIds(const std::string& str, std::vector<uint32_t>* list) {
+  DCHECK(list);
+  for (const base::StringPiece& piece : base::SplitStringPiece(
+           str, ";", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
+    uint32_t id = 0;
+    bool succeed = base::HexStringToUInt(piece, &id);
+    DCHECK(succeed);
+    list->push_back(id);
+  }
+}
+
 }  // namespace anonymous
 
 void MergeFeatureSets(std::set<int>* dst, const std::set<int>& src) {
   DCHECK(dst);
   if (src.empty())
     return;
   dst->insert(src.begin(), src.end());
 }
 
 void ApplyGpuDriverBugWorkarounds(const GPUInfo& gpu_info,
@@ skipping 30 matching lines @@
     command_line->AppendSwitchASCII(switches::kDisableGLExtensions,
                                     base::JoinString(v, " "));
   }
 }
 
 void StringToFeatureSet(
     const std::string& str, std::set<int>* feature_set) {
   StringToIntSet(str, feature_set);
 }
 
+void ParseSecondaryGpuDevicesFromCommandLine(
+    const base::CommandLine& command_line,
+    bool use_testing_switches,

[Zhenyao Mo, 2016/04/21 17:03:37]

I don't think you need this bool.  If testing switches exist, they should always
overwrite the other switches.

[Julien Isorce Samsung, 2016/04/21 23:27:08]

Done.

+    GPUInfo* gpu_info) {
+  const char* secondary_vendor_ids_key = switches::kGpuSecondaryVendorIDs;
+  const char* secondary_device_ids_key = switches::kGpuSecondaryDeviceIDs;
+
+  if (use_testing_switches) {
+    secondary_vendor_ids_key = switches::kGpuTestingSecondaryVendorIDs;
+    secondary_device_ids_key = switches::kGpuTestingSecondaryDeviceIDs;
+  }
+
+  if (!command_line.HasSwitch(secondary_vendor_ids_key) ||
+      !command_line.HasSwitch(secondary_device_ids_key)) {
+    return;
+  }
+
+  std::vector<uint32_t> vendor_ids;
+  std::vector<uint32_t> device_ids;
+  StringToIds(command_line.GetSwitchValueASCII(secondary_vendor_ids_key),
+              &vendor_ids);
+  StringToIds(command_line.GetSwitchValueASCII(secondary_device_ids_key),
+              &device_ids);
+
+  DCHECK(vendor_ids.size() == device_ids.size());
+  gpu_info->secondary_gpus.clear();
+  for (size_t i = 0; i < vendor_ids.size() && i < device_ids.size(); ++i) {
+    gpu::GPUInfo::GPUDevice secondary_device;
+    secondary_device.active = false;
+    secondary_device.vendor_id = vendor_ids[i];
+    secondary_device.device_id = device_ids[i];
+    gpu_info->secondary_gpus.push_back(secondary_device);
+  }
+}
+
 }  // namespace gpu