Add a "disabled" field for GPU Blacklist entries.

content/browser/gpu/gpu_data_manager.cc

Index: content/browser/gpu/gpu_data_manager.cc
===================================================================
--- content/browser/gpu/gpu_data_manager.cc	(revision 102158)
+++ content/browser/gpu/gpu_data_manager.cc	(working copy)
@@ -408,13 +408,14 @@
 
   uint32 flags = gpu_feature_flags_.flags();
   uint32 max_entry_id = gpu_blacklist->max_entry_id();
+  bool disabled = false;
   if (flags == 0) {
     UMA_HISTOGRAM_ENUMERATION("GPU.BlacklistTestResultsPerEntry",
         0, max_entry_id + 1);
   } else {
     std::vector<uint32> flag_entries;
     gpu_blacklist->GetGpuFeatureFlagEntries(
-        GpuFeatureFlags::kGpuFeatureAll, flag_entries);
+        GpuFeatureFlags::kGpuFeatureAll, flag_entries, disabled);
     DCHECK_GT(flag_entries.size(), 0u);
     for (size_t i = 0; i < flag_entries.size(); ++i) {
       UMA_HISTOGRAM_ENUMERATION("GPU.BlacklistTestResultsPerEntry",
@@ -422,6 +423,17 @@
     }
   }
 
+  // This counts how many users are affected by a disabled entry - this allows
+  // us to understand the impact of an entry before enable it.
+  std::vector<uint32> flag_disabled_entries;
+  disabled = true;
+  gpu_blacklist->GetGpuFeatureFlagEntries(
+      GpuFeatureFlags::kGpuFeatureAll, flag_disabled_entries, disabled);
+  for (size_t i = 0; i < flag_disabled_entries.size(); ++i) {
+    UMA_HISTOGRAM_ENUMERATION("GPU.BlacklistTestResultsPerDisabledEntry",
+        flag_disabled_entries[i], max_entry_id + 1);
+  }
+
   const GpuFeatureFlags::GpuFeatureType kGpuFeatures[] = {
       GpuFeatureFlags::kGpuFeatureAccelerated2dCanvas,
       GpuFeatureFlags::kGpuFeatureAcceleratedCompositing,