Add method for suppressing MemoryPressureListener notifications

base/memory/memory_pressure_listener_unittest.cc

+// Copyright 2015 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 "base/memory/memory_pressure_listener.h"
+
+#include "base/bind.h"
+#include "base/message_loop/message_loop.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+namespace base {
+
+using MockCallback =
+    testing::MockFunction<void(MemoryPressureListener::MemoryPressureLevel)>;
+
+TEST(MemoryPressureListenerTest, NotifyMemoryPressure) {
+  MessageLoopForUI message_loop;
+  MockCallback callback;
+  scoped_ptr<MemoryPressureListener> listener(new MemoryPressureListener(
+      Bind(&MockCallback::Call, Unretained(&callback))));
+
+  // Memory pressure notifications are not suppressed by default.
+  EXPECT_FALSE(MemoryPressureListener::AreNotificationsSuppressed());
+  EXPECT_CALL(callback,
+              Call(MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE))
+      .Times(1);
+  MemoryPressureListener::NotifyMemoryPressure(
+      MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE);
+  message_loop.RunUntilIdle();
+
+  // Enable suppressing memory pressure notifications.
+  MemoryPressureListener::SetNotificationsSuppressed(true);
+  EXPECT_TRUE(MemoryPressureListener::AreNotificationsSuppressed());
+  EXPECT_CALL(callback, Call(testing::_)).Times(0);
+  MemoryPressureListener::NotifyMemoryPressure(
+      MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE);
+  message_loop.RunUntilIdle();
+
+  // Disable suppressing memory pressure notifications.
+  MemoryPressureListener::SetNotificationsSuppressed(false);
+  EXPECT_FALSE(MemoryPressureListener::AreNotificationsSuppressed());
+  EXPECT_CALL(callback,
+              Call(MemoryPressureListener::MEMORY_PRESSURE_LEVEL_CRITICAL))
+      .Times(1);
+  MemoryPressureListener::NotifyMemoryPressure(
+      MemoryPressureListener::MEMORY_PRESSURE_LEVEL_CRITICAL);
+  message_loop.RunUntilIdle();
+
+  listener.reset();
+}
+
+}  // namespace base