Add field trial for vp8 cpu speed configuration for arm.

Bug: none
Change-Id: I90c2475a229a1f10016e2ad84029e19b5a4f9966
Reviewed-on: https://webrtc-review.googlesource.com/c/107340
Commit-Queue: Åsa Persson <asapersson@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25484}
diff --git a/rtc_base/experiments/cpu_speed_experiment_unittest.cc b/rtc_base/experiments/cpu_speed_experiment_unittest.cc
new file mode 100644
index 0000000..edc782c
--- /dev/null
+++ b/rtc_base/experiments/cpu_speed_experiment_unittest.cc
@@ -0,0 +1,85 @@
+/*
+ *  Copyright 2018 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "rtc_base/experiments/cpu_speed_experiment.h"
+
+#include "rtc_base/gunit.h"
+#include "test/field_trial.h"
+#include "test/gmock.h"
+
+namespace webrtc {
+
+TEST(CpuSpeedExperimentTest, GetConfigsFailsIfNotEnabled) {
+  EXPECT_FALSE(CpuSpeedExperiment::GetConfigs());
+}
+
+TEST(CpuSpeedExperimentTest, GetConfigsFailsForTooFewParameters) {
+  webrtc::test::ScopedFieldTrials field_trials(
+      "WebRTC-VP8-CpuSpeed-Arm/Enabled-1000,-1,2000,-10,3000/");
+  EXPECT_FALSE(CpuSpeedExperiment::GetConfigs());
+}
+
+TEST(CpuSpeedExperimentTest, GetConfigs) {
+  webrtc::test::ScopedFieldTrials field_trials(
+      "WebRTC-VP8-CpuSpeed-Arm/Enabled-1000,-1,2000,-10,3000,-16/");
+
+  const absl::optional<std::vector<CpuSpeedExperiment::Config>> kConfigs =
+      CpuSpeedExperiment::GetConfigs();
+  ASSERT_TRUE(kConfigs);
+  EXPECT_THAT(*kConfigs,
+              ::testing::ElementsAre(CpuSpeedExperiment::Config{1000, -1},
+                                     CpuSpeedExperiment::Config{2000, -10},
+                                     CpuSpeedExperiment::Config{3000, -16}));
+}
+
+TEST(CpuSpeedExperimentTest, GetValue) {
+  webrtc::test::ScopedFieldTrials field_trials(
+      "WebRTC-VP8-CpuSpeed-Arm/Enabled-1000,-5,2000,-10,3000,-12/");
+
+  const absl::optional<std::vector<CpuSpeedExperiment::Config>> kConfigs =
+      CpuSpeedExperiment::GetConfigs();
+  ASSERT_TRUE(kConfigs);
+  ASSERT_EQ(3u, (*kConfigs).size());
+  EXPECT_EQ(-5, CpuSpeedExperiment::GetValue(1, *kConfigs));
+  EXPECT_EQ(-5, CpuSpeedExperiment::GetValue(1000, *kConfigs));
+  EXPECT_EQ(-10, CpuSpeedExperiment::GetValue(1000 + 1, *kConfigs));
+  EXPECT_EQ(-10, CpuSpeedExperiment::GetValue(2000, *kConfigs));
+  EXPECT_EQ(-12, CpuSpeedExperiment::GetValue(2000 + 1, *kConfigs));
+  EXPECT_EQ(-12, CpuSpeedExperiment::GetValue(3000, *kConfigs));
+  EXPECT_EQ(-16, CpuSpeedExperiment::GetValue(3000 + 1, *kConfigs));
+}
+
+TEST(CpuSpeedExperimentTest, GetConfigsFailsForTooSmallValue) {
+  // Supported range: [-16, -1].
+  webrtc::test::ScopedFieldTrials field_trials(
+      "WebRTC-VP8-CpuSpeed-Arm/Enabled-1000,-1,2000,-10,3000,-17/");
+  EXPECT_FALSE(CpuSpeedExperiment::GetConfigs());
+}
+
+TEST(CpuSpeedExperimentTest, GetConfigsFailsForTooLargeValue) {
+  // Supported range: [-16, -1].
+  webrtc::test::ScopedFieldTrials field_trials(
+      "WebRTC-VP8-CpuSpeed-Arm/Enabled-1000,0,2000,-10,3000,-16/");
+  EXPECT_FALSE(CpuSpeedExperiment::GetConfigs());
+}
+
+TEST(CpuSpeedExperimentTest, GetConfigsFailsIfPixelsDecreasing) {
+  webrtc::test::ScopedFieldTrials field_trials(
+      "WebRTC-VP8-CpuSpeed-Arm/Enabled-1000,-5,999,-10,3000,-16/");
+  EXPECT_FALSE(CpuSpeedExperiment::GetConfigs());
+}
+
+TEST(CpuSpeedExperimentTest, GetConfigsFailsIfCpuSpeedIncreasing) {
+  webrtc::test::ScopedFieldTrials field_trials(
+      "WebRTC-VP8-CpuSpeed-Arm/Enabled-1000,-5,2000,-4,3000,-16/");
+  EXPECT_FALSE(CpuSpeedExperiment::GetConfigs());
+}
+
+}  // namespace webrtc