Adding method IsInBeam to beamformer class.

webrtc/modules/audio_processing/beamformer/beamformer.h

Index: webrtc/modules/audio_processing/beamformer/beamformer.h
diff --git a/webrtc/modules/audio_processing/beamformer/beamformer.h b/webrtc/modules/audio_processing/beamformer/beamformer.h
index 04cb659c6d346954e23feef5af5613cbfa4af5e3..f31955448c0f59e25785b125881e0229df134e4c 100644
--- a/webrtc/modules/audio_processing/beamformer/beamformer.h
+++ b/webrtc/modules/audio_processing/beamformer/beamformer.h
@@ -31,6 +31,9 @@ class Beamformer {
   // Needs to be called before the the Beamformer can be used.
   virtual void Initialize(int chunk_size_ms, int sample_rate_hz) = 0;
 
+  // Indicates whether a given azimuth is inside of the beam.
+  virtual bool IsInBeam(SphericalPointf spherical_point) { return true; }

[Andrew MacDonald, 2015/06/26 02:04:24]

Do we want to make this pure virtual after we update derived classes? If so, add
a TODO.

Doesn't really matter with such a small type, but make it a const reference:
const SphericalPointf& spherical_point

[bloch, 2015/06/26 03:37:28]

I'm not sure. I like the logic of assuming "true" unless otherwise specified, so
every class that inherits from beamformer can accommodate a call to "IsInBeam".
Someone who implements a weak beamformer with no "outside of beam" area
shouldn't have to write their own version that always returns true. WDYT?
Done. 

[Andrew MacDonald, 2015/06/26 03:46:09]

I'd argue the creator of such a beamformer _should_ be forced to implement this.
No big deal though, you can leave it as-is.

+
   // Returns true if the current data contains the target signal.
   // Which signals are considered "targets" is implementation dependent.
   virtual bool is_target_present() = 0;