Renderer changes for wiring up shared memory with declarative injection

extensions/renderer/user_script_set_manager.cc

Index: extensions/renderer/user_script_set_manager.cc
diff --git a/extensions/renderer/user_script_set_manager.cc b/extensions/renderer/user_script_set_manager.cc
index 6aa22d91dc8351ceac92d7d4889790c521eb0163..b0fac93df528de94b45e12da8d350d3d30ae4503 100644
--- a/extensions/renderer/user_script_set_manager.cc
+++ b/extensions/renderer/user_script_set_manager.cc
@@ -30,6 +30,26 @@ void UserScriptSetManager::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
 }
 
+scoped_ptr<ScriptInjection> UserScriptSetManager::GetInjectionForScript(
+      int64 script_id,
+      blink::WebFrame* web_frame,
+      int tab_id,
+      UserScript::RunLocation run_location,
+      const GURL& url,
+      const Extension* extension) {
+  UserScriptSet* user_script_set =
+      GetProgrammaticScriptsByExtension(extension->id());
+  if (!user_script_set)
+    return scoped_ptr<ScriptInjection>();
+
+  return user_script_set->GetInjectionByScriptID(script_id,
+                                                 web_frame,
+                                                 tab_id,
+                                                 run_location,
+                                                 url,
+                                                 extension);
+}
+
 bool UserScriptSetManager::OnControlMessageReceived(
     const IPC::Message& message) {
   bool handled = true;
@@ -40,13 +60,6 @@ bool UserScriptSetManager::OnControlMessageReceived(
   return handled;
 }
 
-const UserScriptSet* UserScriptSetManager::GetProgrammaticScriptsByExtension(
-    const ExtensionId& extension_id) {
-  UserScriptSetMap::const_iterator it =
-      programmatic_scripts_.find(extension_id);
-  return it != programmatic_scripts_.end() ? it->second.get() : NULL;
-}
-
 void UserScriptSetManager::GetAllInjections(
     ScopedVector<ScriptInjection>* injections,
     blink::WebFrame* web_frame,
@@ -71,6 +84,13 @@ void UserScriptSetManager::GetAllActiveExtensionIds(
   }
 }
 
+UserScriptSet* UserScriptSetManager::GetProgrammaticScriptsByExtension(
+    const ExtensionId& extension_id) {
+  UserScriptSetMap::const_iterator it =
+      programmatic_scripts_.find(extension_id);
+  return it != programmatic_scripts_.end() ? it->second.get() : NULL;
+}
+
 void UserScriptSetManager::OnUpdateUserScripts(
     base::SharedMemoryHandle shared_memory,
     const ExtensionId& extension_id,
@@ -91,10 +111,6 @@ void UserScriptSetManager::OnUpdateUserScripts(
 
   UserScriptSet* scripts = NULL;
   if (!extension_id.empty()) {
-    // The expectation when there is an extensions that "owns" this shared
-    // memory region is that it will list itself as the only changed extension.
-    CHECK(changed_extensions.size() == 1 &&
-          changed_extensions.find(extension_id) != changed_extensions.end());
     if (programmatic_scripts_.find(extension_id) ==
         programmatic_scripts_.end()) {
       scripts = new UserScriptSet(extensions_);
@@ -113,7 +129,14 @@ void UserScriptSetManager::OnUpdateUserScripts(
   const std::set<std::string>* effective_extensions = &changed_extensions;
   std::set<std::string> all_extensions;
   if (changed_extensions.empty()) {
-    all_extensions = extensions_->GetIDs();
+    // The meaning of "all extensions" varies, depending on whether some
+    // extension "owns" this shared memory region.
+    // No owner => all known extensions.
+    // Owner    => just the owner extension.
+    if (extension_id.empty())
+      all_extensions = extensions_->GetIDs();
+    else
+      all_extensions.insert(extension_id);
     effective_extensions = &all_extensions;
   }