Add architecture for simulating memory pressure notifications in all processes

content/browser/memory/memory_pressure_controller_browsertest.cc

Index: content/browser/memory/memory_pressure_controller_browsertest.cc
diff --git a/content/browser/memory/memory_pressure_controller_browsertest.cc b/content/browser/memory/memory_pressure_controller_browsertest.cc
index b1452d84ae122324a94d6658f33307e0d9d5f477..36da0f866a2d33f24a4e3f9e9e09bde617b3f6ef 100644
--- a/content/browser/memory/memory_pressure_controller_browsertest.cc
+++ b/content/browser/memory/memory_pressure_controller_browsertest.cc
@@ -15,6 +15,11 @@
 
 namespace content {
 
+const auto MEMORY_PRESSURE_LEVEL_MODERATE =

[Primiano Tucci (use gerrit), 2015/09/28 12:47:32]

you could move these two lines in the test that needs them

[petrcermak, 2015/09/28 15:39:32]

Done.

+    MemoryPressureLevel::MEMORY_PRESSURE_LEVEL_MODERATE;
+const auto MEMORY_PRESSURE_LEVEL_CRITICAL =
+    MemoryPressureLevel::MEMORY_PRESSURE_LEVEL_CRITICAL;
+
 MATCHER_P(IsSetSuppressedMessage, suppressed, "") {
   // Ensure that the message is deleted upon return.
   scoped_ptr<IPC::Message> message(arg);
@@ -27,6 +32,17 @@ MATCHER_P(IsSetSuppressedMessage, suppressed, "") {
   return suppressed == base::get<0>(param);
 }
 
+MATCHER_P(IsSimulateMessage, level, "") {
+  // Ensure that the message is deleted upon return.
+  scoped_ptr<IPC::Message> message(arg);
+  if (message == nullptr)
+    return false;
+  MemoryMsg_SimulatePressureNotification::Param param;
+  if (!MemoryMsg_SimulatePressureNotification::Read(message.get(), &param))
+    return false;
+  return level == base::get<0>(param);
+}
+
 class MemoryMessageFilterForTesting : public MemoryMessageFilter {
  public:
   MOCK_METHOD1(Send, bool(IPC::Message* message));
@@ -62,6 +78,9 @@ class MemoryMessageFilterForTesting : public MemoryMessageFilter {
 };
 
 class MemoryPressureControllerBrowserTest : public ContentBrowserTest {
+ public:
+  MOCK_METHOD1(OnMemoryPressure, void(MemoryPressureLevel level));
+
  protected:
   void SetPressureNotificationsSuppressedInAllProcessesAndWait(
       bool suppressed) {
@@ -69,6 +88,13 @@ class MemoryPressureControllerBrowserTest : public ContentBrowserTest {
         ->SetPressureNotificationsSuppressedInAllProcesses(suppressed);
     RunAllPendingInMessageLoop(BrowserThread::IO);
   }
+
+  void SimulatePressureNotificationInAllProcessesAndWait(
+      MemoryPressureLevel level) {
+    MemoryPressureController::GetInstance()
+        ->SimulatePressureNotificationInAllProcesses(level);
+    RunAllPendingInMessageLoop(BrowserThread::IO);
+  }
 };
 
 IN_PROC_BROWSER_TEST_F(MemoryPressureControllerBrowserTest,
@@ -128,4 +154,51 @@ IN_PROC_BROWSER_TEST_F(MemoryPressureControllerBrowserTest,
   EXPECT_FALSE(base::MemoryPressureListener::AreNotificationsSuppressed());
 }
 
+IN_PROC_BROWSER_TEST_F(MemoryPressureControllerBrowserTest,
+                       SimulatePressureNotificationInAllProcesses) {
+  scoped_refptr<MemoryMessageFilterForTesting> filter(
+      new MemoryMessageFilterForTesting);
+  scoped_ptr<base::MemoryPressureListener> listener(
+      new base::MemoryPressureListener(
+          base::Bind(&MemoryPressureControllerBrowserTest::OnMemoryPressure,
+                     base::Unretained(this))));
+
+  NavigateToURL(shell(), GetTestUrl("", "title.html"));
+
+  filter->Add();
+
+  EXPECT_CALL(*filter, Send(IsSimulateMessage(MEMORY_PRESSURE_LEVEL_CRITICAL)))
+      .Times(1);
+  EXPECT_CALL(*this, OnMemoryPressure(MEMORY_PRESSURE_LEVEL_CRITICAL)).Times(1);
+  SimulatePressureNotificationInAllProcessesAndWait(
+      MEMORY_PRESSURE_LEVEL_CRITICAL);
+  RunAllPendingInMessageLoop();  // Force the listener to run.

[Primiano Tucci (use gerrit), 2015/09/28 12:47:32]

I'd reword the coomment to  "Wait for the listener"
This is not really "forcing" 

[petrcermak, 2015/09/28 15:39:32]

Done.

+
+  // Enable suppressing memory pressure notifications in all processes. This
+  // should have no impact on simulating memory pressure notifications.
+  EXPECT_CALL(*filter, Send(IsSetSuppressedMessage(true))).Times(1);
+  SetPressureNotificationsSuppressedInAllProcessesAndWait(true);
+
+  EXPECT_CALL(*filter, Send(IsSimulateMessage(MEMORY_PRESSURE_LEVEL_MODERATE)))
+      .Times(1);
+  EXPECT_CALL(*this, OnMemoryPressure(MEMORY_PRESSURE_LEVEL_MODERATE)).Times(1);
+  SimulatePressureNotificationInAllProcessesAndWait(
+      MEMORY_PRESSURE_LEVEL_MODERATE);
+  RunAllPendingInMessageLoop();  // Force the listener to run.
+
+  // Disable suppressing memory pressure notifications in all processes. This
+  // should have no impact on simulating memory pressure notifications.
+  EXPECT_CALL(*filter, Send(IsSetSuppressedMessage(false))).Times(1);
+  SetPressureNotificationsSuppressedInAllProcessesAndWait(false);
+
+  EXPECT_CALL(*filter, Send(IsSimulateMessage(MEMORY_PRESSURE_LEVEL_MODERATE)))
+      .Times(1);
+  EXPECT_CALL(*this, OnMemoryPressure(MEMORY_PRESSURE_LEVEL_MODERATE)).Times(1);
+  SimulatePressureNotificationInAllProcessesAndWait(
+      MEMORY_PRESSURE_LEVEL_MODERATE);
+  RunAllPendingInMessageLoop();  // Force the listener to run.
+
+  filter->Remove();
+}
+
 }  // namespace content