Update MockVideoEncoder with correct methods.

Add GetEncoderInfo() and remove HasTrustedRateController(), which was
erroneously added here:
https://webrtc-review.googlesource.com/c/src/+/105620

Bug: webrtc:9722
Change-Id: Iaff6eed773c3431b806adb694b6e3564b180188e
Reviewed-on: https://webrtc-review.googlesource.com/c/109586
Reviewed-by: Per Kjellander <perkj@webrtc.org>
Commit-Queue: Erik Språng <sprang@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25541}

api/test/mock_video_encoder.h

@@ -49,7 +49,7 @@ class MockVideoEncoder : public VideoEncoder {
   MOCK_METHOD2(SetRateAllocation,
                int32_t(const VideoBitrateAllocation& newBitRate,
                        uint32_t frameRate));
-  MOCK_CONST_METHOD0(HasTrustedRateController, bool(void));
+  MOCK_CONST_METHOD0(GetEncoderInfo, EncoderInfo(void));
 };
 
 }  // namespace webrtc