Refactor ResourceHandler API.

content/browser/loader/throttling_resource_handler.cc

Index: content/browser/loader/throttling_resource_handler.cc
diff --git a/content/browser/loader/throttling_resource_handler.cc b/content/browser/loader/throttling_resource_handler.cc
index cf8ad2247c1f47a9dceb633080ab22195ab27a2f..53ac66a86be03386ff646c160e04c02ade46b054 100644
--- a/content/browser/loader/throttling_resource_handler.cc
+++ b/content/browser/loader/throttling_resource_handler.cc
@@ -33,77 +33,91 @@ ThrottlingResourceHandler::ThrottlingResourceHandler(
 ThrottlingResourceHandler::~ThrottlingResourceHandler() {
 }
 
-bool ThrottlingResourceHandler::OnRequestRedirected(
+void ThrottlingResourceHandler::OnRequestRedirected(
     const net::RedirectInfo& redirect_info,
     ResourceResponse* response,
-    bool* defer) {
+    bool* defer_or_cancel) {
   DCHECK(!cancelled_by_resource_throttle_);
 
-  *defer = false;
+  *defer_or_cancel = false;
   while (next_index_ < throttles_.size()) {
     int index = next_index_;
-    throttles_[index]->WillRedirectRequest(redirect_info, defer);
+    throttles_[index]->WillRedirectRequest(redirect_info, defer_or_cancel);
     next_index_++;
-    if (cancelled_by_resource_throttle_)
-      return false;
-    if (*defer) {
+    if (cancelled_by_resource_throttle_) {
+      // Nothing else to do here, already told controller() to cancel the
+      // request.
+      *defer_or_cancel = true;
+      return;
+    }
+    if (*defer_or_cancel) {
       OnRequestDefered(index);
       deferred_stage_ = DEFERRED_REDIRECT;
       deferred_redirect_ = redirect_info;
       deferred_response_ = response;
-      return true;  // Do not cancel.
+      return;
     }
   }
 
   next_index_ = 0;  // Reset for next time.
 
-  return next_handler_->OnRequestRedirected(redirect_info, response, defer);
+  return next_handler_->OnRequestRedirected(redirect_info, response,
+                                            defer_or_cancel);
 }
 
-bool ThrottlingResourceHandler::OnWillStart(const GURL& url, bool* defer) {
+void ThrottlingResourceHandler::OnWillStart(const GURL& url,
+                                            bool* defer_or_cancel) {
   DCHECK(!cancelled_by_resource_throttle_);
 
-  *defer = false;
+  *defer_or_cancel = false;
   while (next_index_ < throttles_.size()) {
     int index = next_index_;
-    throttles_[index]->WillStartRequest(defer);
+    throttles_[index]->WillStartRequest(defer_or_cancel);
     next_index_++;
-    if (cancelled_by_resource_throttle_)
-      return false;
-    if (*defer) {
+    if (cancelled_by_resource_throttle_) {
+      // Nothing else to do here, already told controller() to cancel the
+      // request.
+      *defer_or_cancel = true;
+      return;
+    }
+    if (*defer_or_cancel) {
       OnRequestDefered(index);
       deferred_stage_ = DEFERRED_START;
       deferred_url_ = url;
-      return true;  // Do not cancel.
+      return;
     }
   }
 
   next_index_ = 0;  // Reset for next time.
 
-  return next_handler_->OnWillStart(url, defer);
+  next_handler_->OnWillStart(url, defer_or_cancel);
 }
 
-bool ThrottlingResourceHandler::OnResponseStarted(ResourceResponse* response,
-                                                  bool* defer) {
+void ThrottlingResourceHandler::OnResponseStarted(ResourceResponse* response,
+                                                  bool* defer_or_cancel) {
   DCHECK(!cancelled_by_resource_throttle_);
 
   while (next_index_ < throttles_.size()) {
     int index = next_index_;
-    throttles_[index]->WillProcessResponse(defer);
+    throttles_[index]->WillProcessResponse(defer_or_cancel);
     next_index_++;
-    if (cancelled_by_resource_throttle_)
-      return false;
-    if (*defer) {
+    if (cancelled_by_resource_throttle_) {
+      // Nothing else to do here, already told controller() to cancel the
+      // request.
+      *defer_or_cancel = true;
+      return;
+    }
+    if (*defer_or_cancel) {
       OnRequestDefered(index);
       deferred_stage_ = DEFERRED_RESPONSE;
       deferred_response_ = response;
-      return true;  // Do not cancel.
+      return;
     }
   }
 
   next_index_ = 0;  // Reset for next time.
 
-  return next_handler_->OnResponseStarted(response, defer);
+  return next_handler_->OnResponseStarted(response, defer_or_cancel);
 }
 
 void ThrottlingResourceHandler::Cancel() {
@@ -150,12 +164,10 @@ void ThrottlingResourceHandler::ResumeStart() {
   GURL url = deferred_url_;
   deferred_url_ = GURL();
 
-  bool defer = false;
-  if (!OnWillStart(url, &defer)) {
-    controller()->Cancel();
-  } else if (!defer) {
+  bool defer_or_cancel = false;
+  OnWillStart(url, &defer_or_cancel);
+  if (!defer_or_cancel)
     controller()->Resume();
-  }
 }
 
 void ThrottlingResourceHandler::ResumeRedirect() {
@@ -166,12 +178,10 @@ void ThrottlingResourceHandler::ResumeRedirect() {
   scoped_refptr<ResourceResponse> response;
   deferred_response_.swap(response);
 
-  bool defer = false;
-  if (!OnRequestRedirected(redirect_info, response.get(), &defer)) {
-    controller()->Cancel();
-  } else if (!defer) {
+  bool defer_or_cancel = false;
+  OnRequestRedirected(redirect_info, response.get(), &defer_or_cancel);
+  if (!defer_or_cancel)
     controller()->Resume();
-  }
 }
 
 void ThrottlingResourceHandler::ResumeResponse() {
@@ -180,12 +190,10 @@ void ThrottlingResourceHandler::ResumeResponse() {
   scoped_refptr<ResourceResponse> response;
   deferred_response_.swap(response);
 
-  bool defer = false;
-  if (!OnResponseStarted(response.get(), &defer)) {
-    controller()->Cancel();
-  } else if (!defer) {
+  bool defer_or_cancel = false;
+  OnResponseStarted(response.get(), &defer_or_cancel);
+  if (!defer_or_cancel)
     controller()->Resume();
-  }
 }
 
 void ThrottlingResourceHandler::OnRequestDefered(int throttle_index) {