Use movable types for CallStackProfile(s) to remove copying of data.

components/metrics/child_call_stack_profile_collector_unittest.cc

Index: components/metrics/child_call_stack_profile_collector_unittest.cc
diff --git a/components/metrics/child_call_stack_profile_collector_unittest.cc b/components/metrics/child_call_stack_profile_collector_unittest.cc
index 556124feed9b152ddd17f055e4b9e3ede5b82677..4af7b095913a7bd54101c97d365352f51e07e8ee 100644
--- a/components/metrics/child_call_stack_profile_collector_unittest.cc
+++ b/components/metrics/child_call_stack_profile_collector_unittest.cc
@@ -35,11 +35,11 @@ class ChildCallStackProfileCollectorTest : public testing::Test {
 
     void Collect(const CallStackProfileParams& params,
                  base::TimeTicks start_timestamp,
-                 const std::vector<CallStackProfile>& profiles) override {
+                 std::vector<CallStackProfile> profiles) override {
       this->profiles.push_back(ChildCallStackProfileCollector::ProfilesState(
           params,
           start_timestamp,
-          profiles));
+          std::move(profiles)));
     }
 
     std::vector<ChildCallStackProfileCollector::ProfilesState> profiles;
@@ -55,8 +55,17 @@ class ChildCallStackProfileCollectorTest : public testing::Test {
 
   void CollectProfiles(

[Mike Wittman, 2016/10/21 18:05:29]

This function can be removed.

[bcwhite, 2016/10/24 13:17:45]

Done.

       const CallStackProfileParams& params,
-      const base::StackSamplingProfiler::CallStackProfiles& profiles) {
-    child_collector_.GetProfilerCallback(params).Run(profiles);
+      base::StackSamplingProfiler::CallStackProfiles profiles) {
+    child_collector_.GetProfilerCallback(params).Run(std::move(profiles));
+  }
+
+  void CollectEmptyProfiles(
+      const CallStackProfileParams& params,
+      size_t profile_count) {
+    base::StackSamplingProfiler::CallStackProfiles profiles;
+    for (size_t i = 0; i < profile_count; ++i)
+      profiles.push_back(base::StackSamplingProfiler::CallStackProfile());
+    child_collector_.GetProfilerCallback(params).Run(std::move(profiles));
   }
 
   const std::vector<ChildCallStackProfileCollector::ProfilesState>&
@@ -77,13 +86,12 @@ TEST_F(ChildCallStackProfileCollectorTest, InterfaceProvided) {
   EXPECT_EQ(0u, profiles().size());
 
   // Add profiles before providing the interface.
-  CollectProfiles(
+  CollectEmptyProfiles(
       CallStackProfileParams(CallStackProfileParams::BROWSER_PROCESS,
                              CallStackProfileParams::UI_THREAD,
                              CallStackProfileParams::JANKY_TASK,
                              CallStackProfileParams::PRESERVE_ORDER),
-      { base::StackSamplingProfiler::CallStackProfile(),
-            base::StackSamplingProfiler::CallStackProfile() });
+      2);
   ASSERT_EQ(1u, profiles().size());
   EXPECT_EQ(CallStackProfileParams::BROWSER_PROCESS,
             profiles()[0].params.process);
@@ -111,12 +119,12 @@ TEST_F(ChildCallStackProfileCollectorTest, InterfaceProvided) {
   // Add profiles after providing the interface. They should also be passed to
   // it.
   receiver_impl_->profiles.clear();
-  CollectProfiles(
+  CollectEmptyProfiles(
       CallStackProfileParams(CallStackProfileParams::GPU_PROCESS,
                              CallStackProfileParams::GPU_MAIN_THREAD,
                              CallStackProfileParams::THREAD_HUNG,
                              CallStackProfileParams::PRESERVE_ORDER),
-      { base::StackSamplingProfiler::CallStackProfile() });
+      1);
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(0u, profiles().size());
   ASSERT_EQ(1u, receiver_impl_->profiles.size());
@@ -138,13 +146,12 @@ TEST_F(ChildCallStackProfileCollectorTest, InterfaceNotProvided) {
   EXPECT_EQ(0u, profiles().size());
 
   // Add profiles before providing a null interface.
-  CollectProfiles(
+  CollectEmptyProfiles(
       CallStackProfileParams(CallStackProfileParams::BROWSER_PROCESS,
                              CallStackProfileParams::UI_THREAD,
                              CallStackProfileParams::JANKY_TASK,
                              CallStackProfileParams::PRESERVE_ORDER),
-      { base::StackSamplingProfiler::CallStackProfile(),
-            base::StackSamplingProfiler::CallStackProfile() });
+      2);
   ASSERT_EQ(1u, profiles().size());
   EXPECT_EQ(CallStackProfileParams::BROWSER_PROCESS,
             profiles()[0].params.process);
@@ -163,12 +170,12 @@ TEST_F(ChildCallStackProfileCollectorTest, InterfaceNotProvided) {
   EXPECT_EQ(0u, profiles().size());
 
   // Add profiles after providing a null interface. They should also be flushed.
-  CollectProfiles(
+  CollectEmptyProfiles(
       CallStackProfileParams(CallStackProfileParams::GPU_PROCESS,
                              CallStackProfileParams::GPU_MAIN_THREAD,
                              CallStackProfileParams::THREAD_HUNG,
                              CallStackProfileParams::PRESERVE_ORDER),
-      { base::StackSamplingProfiler::CallStackProfile() });
+      1);
   EXPECT_EQ(0u, profiles().size());
 }