Add UMA histogram for D3D shader model.

This metric will allow us to determine what percentage of our
Windows ANGLE users are using the D3D11 vs D3D9 back-end. It will
also give us a breakdown of what kind of support there is in the
wild for various GPU configs.

BUG=432267

Review URL: https://codereview.chromium.org/719113003

Cr-Commit-Position: refs/heads/master@{#304107}

1 files changed, 39 insertions, 0 deletions

diff --git a/gpu/config/gpu_info_collector_win.cc b/gpu/config/gpu_info_collector_win.cc
index 53343f6..eabf9b2 100644
--- a/gpu/config/gpu_info_collector_win.cc
+++ b/gpu/config/gpu_info_collector_win.cc
@@ -665,6 +665,45 @@ void MergeGPUInfo(GPUInfo* basic_gpu_info,
     return;
   }
 
+  // Track D3D Shader Model (if available)
+  const std::string& shader_version =
+      context_gpu_info.vertex_shader_version;
+
+  // Only gather if this is the first time we're seeing
+  // a non-empty shader version string.
+  if (!shader_version.empty() &&
+      basic_gpu_info->vertex_shader_version.empty()) {
+
+    // Note: do not reorder, used by UMA_HISTOGRAM below
+    enum ShaderModel {
+      SHADER_MODEL_UNKNOWN,
+      SHADER_MODEL_2_0,
+      SHADER_MODEL_3_0,
+      SHADER_MODEL_4_0,
+      SHADER_MODEL_4_1,
+      SHADER_MODEL_5_0,
+      NUM_SHADER_MODELS
+    };
+
+    ShaderModel shader_model = SHADER_MODEL_UNKNOWN;
+
+    if (shader_version == "5.0") {
+      shader_model = SHADER_MODEL_5_0;
+    } else if (shader_version == "4.1") {
+      shader_model = SHADER_MODEL_4_1;
+    } else if (shader_version == "4.0") {
+      shader_model = SHADER_MODEL_4_0;
+    } else if (shader_version == "3.0") {
+      shader_model = SHADER_MODEL_3_0;
+    } else if (shader_version == "2.0") {
+      shader_model = SHADER_MODEL_2_0;
+    }
+
+    UMA_HISTOGRAM_ENUMERATION("GPU.D3DShaderModel",
+                              shader_model,
+                              NUM_SHADER_MODELS);
+  }
+
   MergeGPUInfoGL(basic_gpu_info, context_gpu_info);
 
   basic_gpu_info->dx_diagnostics = context_gpu_info.dx_diagnostics;