[BlobAsync] Faster shortcuttin, make renderer controller leaky & alive.

content/browser/blob_storage/blob_dispatcher_host.h

Index: content/browser/blob_storage/blob_dispatcher_host.h
diff --git a/content/browser/blob_storage/blob_dispatcher_host.h b/content/browser/blob_storage/blob_dispatcher_host.h
index aedf1438037a4b8444843f59d6723a0394de344b..a2d447ea10755ee922d85dc0cb14a65ff1150a7d 100644
--- a/content/browser/blob_storage/blob_dispatcher_host.h
+++ b/content/browser/blob_storage/blob_dispatcher_host.h
@@ -9,6 +9,7 @@
 #include <string>
 #include <vector>
 
+#include "base/callback_forward.h"
 #include "base/files/file.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
@@ -39,13 +40,19 @@ class ChromeBlobStorageContext;
 
 // This class's responsibility is to listen for and dispatch blob storage
 // messages and handle logistics of blob storage for a single child process.
+// It also makes sure the renderer process sticks around while we transfer
+// blobs.
 // When the child process terminates all blob references attributable to
 // that process go away upon destruction of the instance.
 // This lives in the browser process, is single threaded (IO thread), and there
 // is one per child process.
 class CONTENT_EXPORT BlobDispatcherHost : public BrowserMessageFilter {
  public:
-  explicit BlobDispatcherHost(ChromeBlobStorageContext* blob_storage_context);
+  using SetSuddenTerminationAllowedCallback = base::Callback<void(bool)>;
+
+  explicit BlobDispatcherHost(
+      ChromeBlobStorageContext* blob_storage_context,
+      SetSuddenTerminationAllowedCallback set_sudden_termination_allowed);
 
   // BrowserMessageFilter implementation.
   void OnChannelClosing() override;
@@ -66,6 +73,7 @@ class CONTENT_EXPORT BlobDispatcherHost : public BrowserMessageFilter {
   friend class base::RefCountedThreadSafe<BlobDispatcherHost>;
   friend class BlobDispatcherHostTest;
   FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest, EmptyUUIDs);
+  FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest, MultipleTransfers);
   FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest, SharedMemoryTransfer);
   FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest, OnCancelBuildingBlob);
   FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest,
@@ -126,6 +134,12 @@ class CONTENT_EXPORT BlobDispatcherHost : public BrowserMessageFilter {
   // Unregisters all blobs and urls that were registered in this host.
   void ClearHostFromBlobStorageContext();
 
+  void AllowSuddenTerminationIfBuilderEmpty();
+
+  // Calling this should disable or enable sudden renderer termination. We use
+  // this to keep the renderer alive while blobs are being transferred.
+  SetSuddenTerminationAllowedCallback set_sudden_termination_allowed_;
+
   // Collection of blob ids and a count of how many usages
   // of that id are attributable to this consumer.
   BlobReferenceMap blobs_inuse_map_;