Simplify/Cleanup MediaClient

chrome/renderer/media/chrome_key_systems_provider.cc

Index: chrome/renderer/media/chrome_key_systems_provider.cc
diff --git a/chrome/renderer/media/chrome_key_systems_provider.cc b/chrome/renderer/media/chrome_key_systems_provider.cc
new file mode 100644
index 0000000000000000000000000000000000000000..d53bd9dbe9a4f5ea122fef1251b10957719af85b
--- /dev/null
+++ b/chrome/renderer/media/chrome_key_systems_provider.cc
@@ -0,0 +1,83 @@
+// Copyright 2017 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 "chrome/renderer/media/chrome_key_systems_provider.h"
+
+#include "base/time/default_tick_clock.h"
+#include "chrome/renderer/media/chrome_key_systems.h"
+
+#include "widevine_cdm_version.h"  // In SHARED_INTERMEDIATE_DIR.
+
+namespace chrome {
+
+ChromeKeySystemsProvider::ChromeKeySystemsProvider()
+    : has_updated_(false),
+      is_update_needed_(true),
+      tick_clock_(new base::DefaultTickClock()) {}
+
+ChromeKeySystemsProvider::~ChromeKeySystemsProvider() {}
+
+void ChromeKeySystemsProvider::AddSupportedKeySystems(
+    std::vector<std::unique_ptr<media::KeySystemProperties>>* key_systems) {
+  DCHECK(key_systems);
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  if (!test_provider_.is_null()) {
+    test_provider_.Run(key_systems);
+  } else {
+    AddChromeKeySystems(key_systems);
+  }
+
+  has_updated_ = true;
+  last_update_time_ticks_ = tick_clock_->NowTicks();
+
+// Check whether all potentially supported key systems are supported. If so,
+// no need to update again.
+#if defined(WIDEVINE_CDM_AVAILABLE) && defined(WIDEVINE_CDM_IS_COMPONENT)
+  for (const auto& properties : *key_systems) {
+    if (properties->GetKeySystemName() == kWidevineKeySystem) {
+      is_update_needed_ = false;
+    }
+  }
+#else
+  is_update_needed_ = false;
+#endif
+}
+
+bool ChromeKeySystemsProvider::IsKeySystemsUpdateNeeded() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  // Always needs update if we have never updated, regardless the
+  // |last_update_time_ticks_|'s initial value.
+  if (!has_updated_) {
+    DCHECK(is_update_needed_);
+    return true;
+  }
+
+  if (!is_update_needed_)
+    return false;
+
+  // The update could be expensive. For example, it could involve a sync IPC to
+  // the browser process. Use a minimum update interval to avoid unnecessarily
+  // frequent update.
+  static const int kMinUpdateIntervalInMilliseconds = 1000;
+  if ((tick_clock_->NowTicks() - last_update_time_ticks_).InMilliseconds() <
+      kMinUpdateIntervalInMilliseconds) {
+    return false;
+  }
+
+  return true;
+}
+
+void ChromeKeySystemsProvider::SetTickClockForTesting(
+    std::unique_ptr<base::TickClock> tick_clock) {
+  tick_clock_.swap(tick_clock);
+}
+
+void ChromeKeySystemsProvider::SetProviderDelegateForTesting(
+    const KeySystemsProviderDelegate& test_provider) {
+  test_provider_ = test_provider;
+}
+
+}  // namespace chrome