Adds the UserInputMonitor implementation for Mac.

media/audio/audio_input_controller.cc

Index: media/audio/audio_input_controller.cc
diff --git a/media/audio/audio_input_controller.cc b/media/audio/audio_input_controller.cc
index f7747b9d37fb77b948b34e0daf2e3a8407905f56..2899c79bd6071fdd250c59fcf947dd86f47265de 100644
--- a/media/audio/audio_input_controller.cc
+++ b/media/audio/audio_input_controller.cc
@@ -9,6 +9,10 @@
 #include "media/base/limits.h"
 #include "media/base/scoped_histogram_timer.h"
 
+#if defined(OS_MACOSX)
+#include <ApplicationServices/ApplicationServices.h>
+#endif
+
 namespace {
 const int kMaxInputChannels = 2;
 
@@ -46,6 +50,7 @@ AudioInputController::AudioInputController(EventHandler* handler,
       sync_writer_(sync_writer),
       max_volume_(0.0),
       user_input_monitor_(user_input_monitor),
+      prev_key_down_count_(0),
       key_pressed_(false) {
   DCHECK(creator_loop_.get());
 }
@@ -241,6 +246,11 @@ void AudioInputController::DoRecord() {
   stream_->Start(this);
   handler_->OnRecording(this);
 
+#if defined(OS_MACOSX)
+  prev_key_down_count_ = CGEventSourceCounterForEventType(
+      kCGEventSourceStateHIDSystemState, kCGEventKeyDown);
+#endif  // defined(OS_MACOSX)
+
   if (user_input_monitor_)
     user_input_monitor_->AddKeyStrokeListener(this);
 }
@@ -342,6 +352,15 @@ void AudioInputController::OnData(AudioInputStream* stream, const uint8* data,
     std::swap(key_pressed, key_pressed_);
   }
 
+  #if defined(OS_MACOSX)

[Robert Sesek, 2013/08/22 20:45:16]

nit: #if should not be indented

+    uint32_t current_count = CGEventSourceCounterForEventType(
+        kCGEventSourceStateHIDSystemState, kCGEventKeyDown);
+    if (current_count != prev_key_down_count_) {
+      key_pressed = true;
+    }
+    prev_key_down_count_ = current_count;
+  #endif  // defined(OS_MACOSX)
+
   // Mark data as active to ensure that the periodic calls to
   // DoCheckForNoData() does not report an error to the event handler.
   SetDataIsActive(true);