Enable CPU adaptation by default.

WebRtcVideoEngine2 doesn't support CPU-monitor-based adaptation and as
such requires encoder-time-based CPU adaptation to perform any
adaptation at all.

BUG=4536
R=asapersson@webrtc.org, mflodman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/49679004

Cr-Commit-Position: refs/heads/master@{#9001}

talk/media/webrtc/webrtcvideoengine2.cc

diff --git a/talk/media/webrtc/webrtcvideoengine2.cc b/talk/media/webrtc/webrtcvideoengine2.cc
index 953257f..b2e0941 100644
--- a/talk/media/webrtc/webrtcvideoengine2.cc
+++ b/talk/media/webrtc/webrtcvideoengine2.cc
@@ -641,7 +641,7 @@
 }
 
 void WebRtcVideoChannel2::SetDefaultOptions() {
-  options_.cpu_overuse_detection.Set(false);
+  options_.cpu_overuse_detection.Set(true);
   options_.dscp.Set(false);
   options_.suspend_below_min_bitrate.Set(false);
   options_.video_noise_reduction.Set(true);

talk/media/webrtc/webrtcvideoengine2_unittest.cc

diff --git a/talk/media/webrtc/webrtcvideoengine2_unittest.cc b/talk/media/webrtc/webrtcvideoengine2_unittest.cc
index aabefd6..7add66c 100644
--- a/talk/media/webrtc/webrtcvideoengine2_unittest.cc
+++ b/talk/media/webrtc/webrtcvideoengine2_unittest.cc
@@ -1732,9 +1732,9 @@
   codecs.push_back(codec);
   EXPECT_TRUE(channel_->SetSendCodecs(codecs));
 
-  if (enable_overuse) {
+  if (!enable_overuse) {
     VideoOptions options;
-    options.cpu_overuse_detection.Set(true);
+    options.cpu_overuse_detection.Set(false);
     channel_->SetOptions(options);
   }