Add systemInfo.cpu.onUpdated event implementation.

chrome/browser/extensions/api/system_info_cpu/system_info_cpu_apitest.cc

 // Copyright (c) 2012 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/command_line.h"
 #include "base/message_loop.h"
 #include "chrome/browser/extensions/api/system_info_cpu/cpu_info_provider.h"
 #include "chrome/browser/extensions/extension_apitest.h"
+#include "chrome/browser/extensions/extension_test_message_listener.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/test/base/ui_test_utils.h"
 
 namespace extensions {
 
 using api::experimental_system_info_cpu::CpuInfo;
 
 class MockCpuInfoProviderImpl : public CpuInfoProvider {
  public:
-  MockCpuInfoProviderImpl() {}
+  MockCpuInfoProviderImpl() : num_of_processors_(4) {
+    // Set sampling interval to 200ms for testing.
+    sampling_interval_ = 200;
+  }
   ~MockCpuInfoProviderImpl() {}
 
   virtual bool QueryInfo(CpuInfo* info) OVERRIDE {
     if (!info) return false;
 
-    info->num_of_processors = 4;
+    info->num_of_processors = num_of_processors_;
     info->arch_name = "x86";
     info->model_name = "unknown";
 
     return true;
   }
+
+ private:
+  virtual bool QueryCpuTimePerProcessor(std::vector<CpuTime>* times) OVERRIDE {
+    DCHECK(times);
+
+    times->clear();
+    static int user_step = 3;
+    static int kernel_step = 2;
+    static int idle_step = 1;
+    static int count = 0;
+    for (int i = 0; i < num_of_processors_; i++) {
+      CpuTime time;
+      time.user += user_step * count;
+      time.kernel += kernel_step * count;
+      time.idle += idle_step * count;
+      times->push_back(time);
+
+      count++;
+    }
+    return true;
+  }
+
+  int num_of_processors_;
 };
 
 class SystemInfoCpuApiTest: public ExtensionApiTest {
  public:
   SystemInfoCpuApiTest() {}
   ~SystemInfoCpuApiTest() {}
 
   virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
     ExtensionApiTest::SetUpCommandLine(command_line);
     command_line->AppendSwitch(switches::kEnableExperimentalExtensionApis);
   }
 
   virtual void SetUpInProcessBrowserTestFixture() OVERRIDE {
     ExtensionApiTest::SetUpInProcessBrowserTestFixture();
     message_loop_.reset(new MessageLoop(MessageLoop::TYPE_UI));
-
-    CpuInfoProvider* provider = new MockCpuInfoProviderImpl();
-    // The provider is owned by the single CpuInfoProvider instance.
-    CpuInfoProvider::InitializeForTesting(provider);
   }
 
  private:
   scoped_ptr<MessageLoop> message_loop_;
 };
 
 IN_PROC_BROWSER_TEST_F(SystemInfoCpuApiTest, Cpu) {
+  CpuInfoProvider* provider = new MockCpuInfoProviderImpl();
+  // The provider is owned by the single CpuInfoProvider instance.
+  CpuInfoProvider::InitializeForTesting(provider);
   ASSERT_TRUE(RunExtensionTest("systeminfo/cpu")) << message_;
 }
 
 }  // namespace extensions