Poll is_hardware_accelerated from VideoEncoder instead of VideoEncoderFactory.

Currently, CPU overuse settings for HW encoders are sometimes being used
even though the actual encoder is a SW encoder, e.g. in case of SW fallback
when the encoder is initialized. Polling is_hardware_accelerated after the
encoder has been created and initialized will improve choosing the correct
CPU overuse settings.

Bug: webrtc:10065
Change-Id: Ic6bd67630a040b5a121c13fa63dd074006973929
Reviewed-on: https://webrtc-review.googlesource.com/c/116688
Commit-Queue: Mirta Dvornicic <mirtad@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26266}
diff --git a/media/engine/fake_webrtc_video_engine.h b/media/engine/fake_webrtc_video_engine.h
index 1505f49..6d06923 100644
--- a/media/engine/fake_webrtc_video_engine.h
+++ b/media/engine/fake_webrtc_video_engine.h
@@ -96,6 +96,7 @@
   int32_t Release() override;
   int32_t SetRateAllocation(const webrtc::VideoBitrateAllocation& allocation,
                             uint32_t framerate) override;
+  webrtc::VideoEncoder::EncoderInfo GetEncoderInfo() const override;
 
   bool WaitForInitEncode();
   webrtc::VideoCodec GetCodecSettings();