Add a new audio constraint, 'googHotword', that requests the hotword input

content/renderer/media/media_stream_audio_processor_unittest.cc

Index: content/renderer/media/media_stream_audio_processor_unittest.cc
diff --git a/content/renderer/media/media_stream_audio_processor_unittest.cc b/content/renderer/media/media_stream_audio_processor_unittest.cc
index 3ebaea2373c14c664aa81f5fb76741cca3fc42a3..1dfa2c93cfad0a2049ce3bc87ca2a3dc67172854 100644
--- a/content/renderer/media/media_stream_audio_processor_unittest.cc
+++ b/content/renderer/media/media_stream_audio_processor_unittest.cc
@@ -271,7 +271,8 @@ TEST_F(MediaStreamAudioProcessorTest, VerifyConstraints) {
     MediaAudioConstraints::kGoogExperimentalNoiseSuppression,
     MediaAudioConstraints::kGoogHighpassFilter,
     MediaAudioConstraints::kGoogNoiseSuppression,
-    MediaAudioConstraints::kGoogTypingNoiseDetection
+    MediaAudioConstraints::kGoogTypingNoiseDetection,
+    kMediaStreamAudioHotword
   };
 
   // Verify mandatory constraints.
@@ -344,6 +345,14 @@ TEST_F(MediaStreamAudioProcessorTest, VerifyConstraints) {
     EXPECT_FALSE(audio_constraints.GetProperty(kMediaStreamAudioDucking));
 #endif
   }
+
+  {
+    // |kMediaStreamAudioHotword| is always off by default.
+    MockMediaConstraintFactory constraint_factory;
+    MediaAudioConstraints audio_constraints(
+        constraint_factory.CreateWebMediaConstraints(), 0);
+    EXPECT_FALSE(audio_constraints.GetProperty(kMediaStreamAudioHotword));
+  }
 }
 
 TEST_F(MediaStreamAudioProcessorTest, ValidateConstraints) {