Pass Callback to TaskRunner by value and consume it on invocation (1)

ios/web/web_thread_impl.cc

Index: ios/web/web_thread_impl.cc
diff --git a/ios/web/web_thread_impl.cc b/ios/web/web_thread_impl.cc
index eaab3d9e3ff54132b15fa085a3400fa303df422b..d03e29dfb37d28ec6cca0b6b3ee33858aed81e85 100644
--- a/ios/web/web_thread_impl.cc
+++ b/ios/web/web_thread_impl.cc
@@ -49,15 +49,16 @@ class WebThreadTaskRunner : public base::SingleThreadTaskRunner {
 
   // SingleThreadTaskRunner implementation.
   bool PostDelayedTask(const tracked_objects::Location& from_here,
-                       const base::Closure& task,
+                       base::Closure task,
                        base::TimeDelta delay) override {
-    return WebThread::PostDelayedTask(id_, from_here, task, delay);
+    return WebThread::PostDelayedTask(id_, from_here, std::move(task), delay);
   }
 
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
-                                  const base::Closure& task,
+                                  base::Closure task,
                                   base::TimeDelta delay) override {
-    return WebThread::PostNonNestableDelayedTask(id_, from_here, task, delay);
+    return WebThread::PostNonNestableDelayedTask(id_, from_here,
+                                                 std::move(task), delay);
   }
 
   bool RunsTasksOnCurrentThread() const override {
@@ -290,7 +291,7 @@ WebThreadImpl::~WebThreadImpl() {
 // static
 bool WebThreadImpl::PostTaskHelper(WebThread::ID identifier,
                                    const tracked_objects::Location& from_here,
-                                   const base::Closure& task,
+                                   base::Closure task,
                                    base::TimeDelta delay,
                                    bool nestable) {
   DCHECK(identifier >= 0 && identifier < ID_COUNT);
@@ -314,10 +315,11 @@ bool WebThreadImpl::PostTaskHelper(WebThread::ID identifier,
                                   : nullptr;
   if (message_loop) {
     if (nestable) {
-      message_loop->task_runner()->PostDelayedTask(from_here, task, delay);
+      message_loop->task_runner()->PostDelayedTask(from_here, std::move(task),
+                                                   delay);
     } else {
-      message_loop->task_runner()->PostNonNestableDelayedTask(from_here, task,
-                                                              delay);
+      message_loop->task_runner()->PostNonNestableDelayedTask(
+          from_here, std::move(task), delay);
     }
   }
 
@@ -329,8 +331,9 @@ bool WebThreadImpl::PostTaskHelper(WebThread::ID identifier,
 
 // static
 bool WebThread::PostBlockingPoolTask(const tracked_objects::Location& from_here,
-                                     const base::Closure& task) {
-  return g_globals.Get().blocking_pool->PostWorkerTask(from_here, task);
+                                     base::Closure task) {
+  return g_globals.Get().blocking_pool->PostWorkerTask(from_here,
+                                                       std::move(task));
 }
 
 // static
@@ -346,9 +349,9 @@ bool WebThread::PostBlockingPoolTaskAndReply(
 bool WebThread::PostBlockingPoolSequencedTask(
     const std::string& sequence_token_name,
     const tracked_objects::Location& from_here,
-    const base::Closure& task) {
+    base::Closure task) {
   return g_globals.Get().blocking_pool->PostNamedSequencedWorkerTask(
-      sequence_token_name, from_here, task);
+      sequence_token_name, from_here, std::move(task));
 }
 
 // static
@@ -406,25 +409,25 @@ bool WebThread::IsMessageLoopValid(ID identifier) {
 // static
 bool WebThread::PostTask(ID identifier,
                          const tracked_objects::Location& from_here,
-                         const base::Closure& task) {
-  return WebThreadImpl::PostTaskHelper(identifier, from_here, task,
+                         base::Closure task) {
+  return WebThreadImpl::PostTaskHelper(identifier, from_here, std::move(task),
                                        base::TimeDelta(), true);
 }
 
 // static
 bool WebThread::PostDelayedTask(ID identifier,
                                 const tracked_objects::Location& from_here,
-                                const base::Closure& task,
+                                base::Closure task,
                                 base::TimeDelta delay) {
-  return WebThreadImpl::PostTaskHelper(identifier, from_here, task, delay,
-                                       true);
+  return WebThreadImpl::PostTaskHelper(identifier, from_here, std::move(task),
+                                       delay, true);
 }
 
 // static
 bool WebThread::PostNonNestableTask(ID identifier,
                                     const tracked_objects::Location& from_here,
-                                    const base::Closure& task) {
-  return WebThreadImpl::PostTaskHelper(identifier, from_here, task,
+                                    base::Closure task) {
+  return WebThreadImpl::PostTaskHelper(identifier, from_here, std::move(task),
                                        base::TimeDelta(), false);
 }
 
@@ -432,10 +435,10 @@ bool WebThread::PostNonNestableTask(ID identifier,
 bool WebThread::PostNonNestableDelayedTask(
     ID identifier,
     const tracked_objects::Location& from_here,
-    const base::Closure& task,
+    base::Closure task,
     base::TimeDelta delay) {
-  return WebThreadImpl::PostTaskHelper(identifier, from_here, task, delay,
-                                       false);
+  return WebThreadImpl::PostTaskHelper(identifier, from_here, std::move(task),
+                                       delay, false);
 }
 
 // static