Change rtc::VideoSinkWants to have target and a max pixel count

webrtc/call/call_perf_tests.cc

Index: webrtc/call/call_perf_tests.cc
diff --git a/webrtc/call/call_perf_tests.cc b/webrtc/call/call_perf_tests.cc
index b6a8fe6047070f50d4f0ba2b4e887f5251c93024..da5ac96de3500c37a67d34046a3e2b7e7b2474da 100644
--- a/webrtc/call/call_perf_tests.cc
+++ b/webrtc/call/call_perf_tests.cc
@@ -490,13 +490,17 @@ TEST_F(CallPerfTest, ReceivesCpuOveruseAndUnderuse) {
                             const rtc::VideoSinkWants& wants) override {
       // First expect CPU overuse. Then expect CPU underuse when the encoder
       // delay has been decreased.
-      if (wants.max_pixel_count) {
+      if (wants.target_pixel_count) {
+        // Target pixel count set indicates we want to move from a lower res
+        // to a higher.

[stefan-webrtc, 2017/02/06 13:39:49]

It's hard to understand why target_pixel_count means increase resolution. Should
it be named differently to make it clear that it can't be used to target a lower
resolution?

[nisse-webrtc, 2017/02/06 13:42:40]

As far as I understand, it could be used to target a lower resolution, but it
would be more advisory than using the max_pixel_count property.

[sprang_webrtc, 2017/02/06 13:49:53]

That's correct. I guess this is a more an integration test of how vie_encoder
requests new resolutions, rather than a test of the sink wants mechanism itself.

[stefan-webrtc, 2017/02/06 14:01:28]

Maybe update the comment to make that clear, i.e.,

"Lower resolution is requested by a VideoSendStream by setting..."

[sprang_webrtc, 2017/02/06 14:44:08]

Done.

+        EXPECT_FALSE(expect_lower_resolution_wants_);
+        observation_complete_.Set();
+      } else if (wants.max_pixel_count) {
+        // No target set, but max is applied indicates we are overusing and want
+        // a lower resolution.
         EXPECT_TRUE(expect_lower_resolution_wants_);
         expect_lower_resolution_wants_ = false;
         encoder_.SetDelay(2);
-      } else if (wants.max_pixel_count_step_up) {
-        EXPECT_FALSE(expect_lower_resolution_wants_);
-        observation_complete_.Set();
       }
     }