Add unit tests for sub-components of CaptureScheduler.

remoting/host/capture_scheduler_unittest.cc

+// Copyright 2013 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 "testing/gtest/include/gtest/gtest.h"
+
+namespace remoting {
+
+static const int kTestInputs[] = { 100, 50, 30, 20, 10, 30, 60, 80 };
+
+TEST(CaptureSchedulerTest, SingleSampleSameTimes) {
+  const int kTestResults[][arraysize(kTestInputs)] = {
+    { 400, 200, 120, 80, 50, 120, 240, 320 }, // One core.
+    { 200, 100, 60, 50, 50, 60, 120, 160 },   // Two cores.
+    { 100, 50, 50, 50, 50, 50, 60, 80 },      // Four cores.
+    { 50, 50, 50, 50, 50, 50, 50, 50 }        // Eight cores.
+  };
+
+  for (size_t i = 0; i < arraysize(kTestResults); ++i) {
+    for (size_t j = 0; j < arraysize(kTestInputs); ++j) {
+      CaptureScheduler scheduler;
+      scheduler.SetNumOfProcessorsForTest(1 << i);
+      scheduler.RecordCaptureTime(
+          base::TimeDelta::FromMilliseconds(kTestInputs[j]));
+      scheduler.RecordEncodeTime(
+          base::TimeDelta::FromMilliseconds(kTestInputs[j]));
+      EXPECT_EQ(kTestResults[i][j],
+                scheduler.NextCaptureDelay().InMilliseconds());
+    }
+  }
+}
+
+TEST(CaptureSchedulerTest, SingleSampleDifferentTimes) {
+  const int kTestResults[][arraysize(kTestInputs)] = {
+    { 360, 220, 120, 60, 60, 120, 220, 360 }, // One core.
+    { 180, 110, 60, 50, 50, 60, 110, 180 },   // Two cores.
+    { 90, 55, 50, 50, 50, 50, 55, 90 },       // Four cores.
+    { 50, 50, 50, 50, 50, 50, 50, 50 }        // Eight cores.
+  };
+
+  for (size_t i = 0; i < arraysize(kTestResults); ++i) {
+    for (size_t j = 0; j < arraysize(kTestInputs); ++j) {
+      CaptureScheduler scheduler;
+      scheduler.SetNumOfProcessorsForTest(1 << i);
+      scheduler.RecordCaptureTime(
+          base::TimeDelta::FromMilliseconds(kTestInputs[j]));
+      scheduler.RecordEncodeTime(
+          base::TimeDelta::FromMilliseconds(
+              kTestInputs[arraysize(kTestInputs) - 1 - j]));
+      EXPECT_EQ(kTestResults[i][j],
+                scheduler.NextCaptureDelay().InMilliseconds());
+    }
+  }
+}
+
+TEST(CaptureSchedulerTest, RollingAverageDifferentTimes) {
+  const int kTestResults[][arraysize(kTestInputs)] = {
+    { 360, 290, 233, 133, 80, 80, 133, 233 }, // One core.

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

nit: How are there values obtained? If CaptureScheduler changes will these
values need to be regenerated by running this test and printing them out?

It might be better to calculate them here, instead of having the expected result
hardcoded.

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

Then we'd just have two copies of the same calculation, though, and having
manually-calculated values here also makes it possible to sanity-check the
numbers by eye.

+    { 180, 145, 116, 66, 50, 50, 66, 116 },   // Two cores.
+    { 90, 72, 58, 50, 50, 50, 50, 58 },       // Four cores.
+    { 50, 50, 50, 50, 50, 50, 50, 50 }        // Eight cores.
+  };
+
+  for (size_t i = 0; i < arraysize(kTestResults); ++i) {
+    CaptureScheduler scheduler;
+    scheduler.SetNumOfProcessorsForTest(1 << i);
+    for (size_t j = 0; j < arraysize(kTestInputs); ++j) {
+      scheduler.RecordCaptureTime(
+          base::TimeDelta::FromMilliseconds(kTestInputs[j]));
+      scheduler.RecordEncodeTime(
+          base::TimeDelta::FromMilliseconds(
+              kTestInputs[arraysize(kTestInputs) - 1 - j]));
+      EXPECT_EQ(kTestResults[i][j],
+                scheduler.NextCaptureDelay().InMilliseconds());
+    }
+  }
+}
+
+}  // namespace remoting