Add unit tests for sub-components of CaptureScheduler.

remoting/host/capture_scheduler.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "remoting/host/capture_scheduler.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/sys_info.h"
@@ skipping 27 matching lines @@
 
 CaptureScheduler::~CaptureScheduler() {
 }
 
 base::TimeDelta CaptureScheduler::NextCaptureDelay() {
   // Delay by an amount chosen such that if capture and encode times
   // continue to follow the averages, then we'll consume the target
   // fraction of CPU across all cores.
   double delay =
       (capture_time_.Average() + encode_time_.Average()) /
       (kRecordingCpuConsumption * num_of_processors_);

[alexeypa (please no reviews), 2013/03/18 19:39:39]

nit: Unrelated to this CL but I think this formula is wrong when there are more
that two processors because we only have two threads. It also does not account
for threads, used by VP8 codec itself.

PS. Cores with hyper-threading enabled should probably count as half of a core.

[Wez, 2013/03/19 23:23:14]

Yes, we should review our scheduling.  There are several issues:
- No matter how many cores there are, there's no point trying to capture faster
than |capture_time_| or |encode_time_|.
- Since we use two encode threads encoding may be taking up to double
|encode_time_|.
- We should avoid varying the capture delay too much and aim for e.g. 60, 30,
15fps depending on capture & encode performance.

 
   if (delay < kMinimumRecordingDelay)
     return base::TimeDelta::FromMilliseconds(kMinimumRecordingDelay);
   return base::TimeDelta::FromMilliseconds(delay);
 }
 
 void CaptureScheduler::RecordCaptureTime(base::TimeDelta capture_time) {
   capture_time_.Record(capture_time.InMilliseconds());
 }
 
 void CaptureScheduler::RecordEncodeTime(base::TimeDelta encode_time) {
   encode_time_.Record(encode_time.InMilliseconds());
 }
 
+void CaptureScheduler::SetNumOfProcessorsForTest(int num_of_processors) {
+  num_of_processors_ = num_of_processors;
+}
+
 }  // namespace remoting