add UMA metrics for voice interaction entries.

chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc

Index: chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc
diff --git a/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc b/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc
index 97f746f60fc83e28d20ef544598de70092f3d14e..46c35cb70a0f15b2925abffdf1293d56677087fa 100644
--- a/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc
+++ b/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc
@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "ash/accelerators/accelerator_controller.h"
+#include "ash/metrics/voice_interaction_metrics.h"
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/shell.h"
 #include "base/bind.h"
@@ -15,6 +16,7 @@
 #include "base/containers/flat_set.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/task_scheduler/post_task.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_list.h"
@@ -122,6 +124,27 @@ void EncodeAndReturnImage(
       callback);
 }
 
+void RecordAcceleratorUmaMetrics(const ui::Accelerator& accelerator) {
+  if (accelerator.IsCmdDown() && accelerator.key_code() == ui::VKEY_A) {
+    if (accelerator.IsShiftDown()) {
+      UMA_HISTOGRAM_ENUMERATION(
+          "VoiceInteraction.MetaLayer.EntryPoints",
+          ash::VoiceInteractionMetaLayerEntry::META_SHIFT_A,

[Daniel Erat, 2017/05/23 22:32:18]

does "meta" here correspond to the search key? if so, please consider using e.g.
SEARCH_SHIFT_A instead. i recommend staying away from the word "meta", since i
think we either use search or "command" to refer to this key in the code and in
user-facing strings.

[Muyuan, 2017/05/24 00:24:54]

Acknowledged.

+          ash::VoiceInteractionMetaLayerEntry::COUNT);
+      return;
+    }
+    UMA_HISTOGRAM_ENUMERATION("VoiceInteraction.EntryPoints",
+                              ash::VoiceInteractionEntry::META_A,
+                              ash::VoiceInteractionEntry::COUNT);
+    return;
+  }
+  if (accelerator.IsCmdDown() && accelerator.key_code() == ui::VKEY_SPACE) {
+    UMA_HISTOGRAM_ENUMERATION("VoiceInteraction.EntryPoints",
+                              ash::VoiceInteractionEntry::META_SPACE,
+                              ash::VoiceInteractionEntry::COUNT);
+  }
+}
+
 }  // namespace
 
 // static
@@ -171,6 +194,8 @@ bool ArcVoiceInteractionFrameworkService::AcceleratorPressed(
     const ui::Accelerator& accelerator) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
+  RecordAcceleratorUmaMetrics(accelerator);
+
   if (accelerator.IsShiftDown()) {
     // Temporary, used for debugging.
     // Does not take into account or update the palette state.