[Extensions] Don't report a bad message if the UUID is legitimate.

Bug: 955657
Change-Id: Id5124d9651d8939b8d4e37f6cfaca5b2561233d1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1579639
Commit-Queue: David Bertoni <dbertoni@chromium.org>
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653659}

extensions/browser/extension_service_worker_message_filter.cc

@@ -73,6 +73,7 @@ void ExtensionServiceWorkerMessageFilter::OnIncrementServiceWorkerActivity(
     int64_t service_worker_version_id,
     const std::string& request_uuid) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+  active_request_uuids_.insert(request_uuid);
   // The worker might have already stopped before we got here, so the increment
   // below might fail legitimately. Therefore, we do not send bad_message to the
   // worker even if it fails.
@@ -86,7 +87,12 @@ void ExtensionServiceWorkerMessageFilter::OnDecrementServiceWorkerActivity(
   DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
   bool status = service_worker_context_->FinishedExternalRequest(
       service_worker_version_id, request_uuid);
-  if (!status) {
+  if (!status)
+    LOG(ERROR) << "ServiceWorkerContext::FinishedExternalRequest failed.";
+  bool erased = active_request_uuids_.erase(request_uuid) == 1;
+  // The worker may have already stopped before we got here, so only report
+  // a bad message if we didn't have an increment for the UUID.
+  if (!erased) {
     bad_message::ReceivedBadMessage(
         this, bad_message::ESWMF_INVALID_DECREMENT_ACTIVITY);
   }

extensions/browser/extension_service_worker_message_filter.h

@@ -5,6 +5,8 @@
 #ifndef EXTENSIONS_BROWSER_EXTENSION_SERVICE_WORKER_MESSAGE_FILTER_H_
 #define EXTENSIONS_BROWSER_EXTENSION_SERVICE_WORKER_MESSAGE_FILTER_H_
 
+#include <unordered_set>
+
 #include "base/macros.h"
 #include "content/public/browser/browser_message_filter.h"
 #include "content/public/browser/browser_thread.h"
@@ -71,6 +73,8 @@ class ExtensionServiceWorkerMessageFilter
                   content::BrowserThread::DeleteOnUIThread>
       dispatcher_;
 
+  std::unordered_set<std::string> active_request_uuids_;
+
   DISALLOW_COPY_AND_ASSIGN(ExtensionServiceWorkerMessageFilter);
 };