-Add a mojo service to get video frames from the camera through an android service

mojo/services/camera/public/interfaces/camera.mojom

Index: mojo/services/camera/public/interfaces/camera.mojom
diff --git a/mojo/services/camera_roll/public/interfaces/camera_roll.mojom b/mojo/services/camera/public/interfaces/camera.mojom
similarity index 88%
rename from mojo/services/camera_roll/public/interfaces/camera_roll.mojom
rename to mojo/services/camera/public/interfaces/camera.mojom
index 850da78f654a6594868e806bd4a30e7f7a782684..b5595cf0e04f1aa92cb05099aae04ca626304b11 100644
--- a/mojo/services/camera_roll/public/interfaces/camera_roll.mojom
+++ b/mojo/services/camera/public/interfaces/camera.mojom
@@ -28,3 +28,8 @@ interface CameraRollService {
   // if such an index is out-of-bounds.
   GetPhoto(uint32 index) => (Photo? photo);
 };
+
+// |CameraService| provides access to the device's camera video stream.
+interface CameraVideoService {

[alhaad1, 2015/10/02 06:33:27]

Could we call it just CameraService? There is nothing video specific about this.
We could use it to capture images as well. (And we could conceivably add finer
control later) 

[gautham, 2015/10/02 22:29:11]

Done.

+  GetVideoFrames() => (handle<data_pipe_consumer>? content);

[alhaad1, 2015/10/02 06:33:27]

This could be GetLatestFrame?

Also, do you think it would be better if we share the struct Photo between the
two?

[gautham, 2015/10/02 22:29:11]

I'm hoping we'll fix the ImageDecoder to work with a streaming data_pipe and
would not have not close/re-open the handle on the sender side. After that we'd
need the return value to be a data_pipe. 

+};