Revert of Ensuring interception of stream get determined by plugin path before checking mime type.

chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc

Index: chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
diff --git a/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc b/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
index f8f35851372015f209d20264123308098f6c205a..1630c3fd98eb814ea5a10b09a7cb8bd3a3d1eacd 100644
--- a/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
+++ b/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
@@ -205,6 +205,36 @@
       extension_id, web_contents, stream.Pass(), view_id, expected_content_size,
       embedded, render_process_id, render_frame_id);
 }
+
+// TODO(raymes): This won't return the right result if plugins haven't been
+// loaded yet. Fixing this properly really requires fixing crbug.com/443466.
+bool IsPluginEnabledForExtension(const Extension* extension,
+                                 const ResourceRequestInfo* info,
+                                 const std::string& mime_type,
+                                 const GURL& url) {
+  content::PluginService* service = content::PluginService::GetInstance();
+  std::vector<content::WebPluginInfo> plugins;
+  service->GetPluginInfoArray(url, mime_type, true, &plugins, nullptr);
+  content::PluginServiceFilter* filter = service->GetFilter();
+
+  for (auto& plugin : plugins) {
+    // Check that the plugin is running the extension.
+    if (plugin.path !=
+        base::FilePath::FromUTF8Unsafe(extension->url().spec())) {
+      continue;
+    }
+    // Check that the plugin is actually enabled.
+    if (!filter || filter->IsPluginAvailable(info->GetChildID(),
+                                             info->GetRenderFrameID(),
+                                             info->GetContext(),
+                                             url,
+                                             GURL(),
+                                             &plugin)) {
+      return true;
+    }
+  }
+  return false;
+}
 #endif  // !defined(ENABLE_EXTENSIONS)
 
 #if !defined(OS_ANDROID)
@@ -571,7 +601,6 @@
 
 bool ChromeResourceDispatcherHostDelegate::ShouldInterceptResourceAsStream(
     net::URLRequest* request,
-    const base::FilePath& plugin_path,
     const std::string& mime_type,
     GURL* origin,
     std::string* payload) {
@@ -595,27 +624,23 @@
          !extension_info_map->IsIncognitoEnabled(extension_id))) {
       continue;
     }
+
     MimeTypesHandler* handler = MimeTypesHandler::GetHandler(extension);
-    // If the MimeHandlerView plugin to be loaded matches the extension,
-    // intercept the stream for that extension.
-    if (plugin_path ==
-        base::FilePath::FromUTF8Unsafe(extension->url().spec())) {
+    if (handler && handler->CanHandleMIMEType(mime_type)) {
       StreamTargetInfo target_info;
       *origin = Extension::GetBaseURLFromExtensionId(extension_id);
       target_info.extension_id = extension_id;
-      DCHECK(!handler->handler_url().empty());
-      target_info.view_id = base::GenerateGUID();
-      *payload = target_info.view_id;
-      stream_target_info_[request] = target_info;
-      return true;
-    } else if (plugin_path.empty() && handler &&
-               handler->CanHandleMIMEType(mime_type)) {
-      // If no plugin path is provided, then we are trying to intercept the
-      // stream for the streamsPrivate API.
-      StreamTargetInfo target_info;
-      *origin = Extension::GetBaseURLFromExtensionId(extension_id);
-      target_info.extension_id = extension_id;
-      DCHECK(handler->handler_url().empty());
+      if (!handler->handler_url().empty()) {
+        // This is reached in the case of MimeHandlerViews. If the
+        // MimeHandlerView plugin is disabled, then we shouldn't intercept the
+        // stream.
+        if (!IsPluginEnabledForExtension(extension, info, mime_type,
+                                         request->url())) {
+          continue;
+        }
+        target_info.view_id = base::GenerateGUID();
+        *payload = target_info.view_id;
+      }
       stream_target_info_[request] = target_info;
       return true;
     }