[telemetry] Process streams of bitmaps via BitmapIter

tools/telemetry/telemetry/core/platform/__init__.py

Index: tools/telemetry/telemetry/core/platform/__init__.py
diff --git a/tools/telemetry/telemetry/core/platform/__init__.py b/tools/telemetry/telemetry/core/platform/__init__.py
index a72004fec6d4ad93576299414d308ed4758c3e88..3a3f3f6457b8f3712a651d9f3c17fa59b436b088 100644
--- a/tools/telemetry/telemetry/core/platform/__init__.py
+++ b/tools/telemetry/telemetry/core/platform/__init__.py
@@ -150,14 +150,9 @@ class Platform(object):
   def StopVideoCapture(self):
     """Stops capturing video.
 
-    Yields:
-      (time_ms, bitmap) tuples representing each video keyframe. Only the first
-      frame in a run of sequential duplicate bitmaps is included.
-        time_ms is milliseconds relative to the first frame.
-        bitmap is a telemetry.core.Bitmap.
+    Returns a telemetry.core.BitmapIter.
     """
-    for t in self._platform_backend.StopVideoCapture():
-      yield t
+    return self._platform_backend.StopVideoCapture()
 
 
 def CreatePlatformBackendForCurrentOS():