Forward MIME types to BrowserPlugin when a viewer is specified.

chrome/browser/extensions/api/streams_private/streams_private_api.h

Index: chrome/browser/extensions/api/streams_private/streams_private_api.h
diff --git a/chrome/browser/extensions/api/streams_private/streams_private_api.h b/chrome/browser/extensions/api/streams_private/streams_private_api.h
index fcf724591518bffbe6ac4ff0df2d5ed7bf2ea128..bbd46ca225bbc6a3d697cf4e1ed7a0caf4a003aa 100644
--- a/chrome/browser/extensions/api/streams_private/streams_private_api.h
+++ b/chrome/browser/extensions/api/streams_private/streams_private_api.h
@@ -30,9 +30,16 @@ class StreamsPrivateAPI : public BrowserContextKeyedAPI,
   explicit StreamsPrivateAPI(content::BrowserContext* context);
   virtual ~StreamsPrivateAPI();
 
+  // Send the onExecuteMimeTypeHandler event to |extension_id|.
+  // |web_contents| is used to determine the tabId where the document is being
+  // opened. The data for the document will be readable from |stream|, and
+  // should be |expected_content_size| bytes long. If the viewer is already
+  // being opened in a BrowserPlugin, |view_id| will be the ID sent to the
+  // viewer.

[not at google - send to devlin, 2014/04/30 15:42:43]

the implementation implies that |web_contents| is ignored with |view_id| is
non-empty. Perhaps it's worth mentioning that (in a non-implementation-detaily
way) like

If the viewer is being opened in a BrowserPlugin, specify a non-empty |view_id|
of the plugin. This takes precedence over the tab ID.

[Zachary Kuznia, 2014/05/01 00:38:22]

Updated the language for view_id.

   void ExecuteMimeTypeHandler(const std::string& extension_id,
                               const content::WebContents* web_contents,
                               scoped_ptr<content::StreamHandle> stream,
+                              const std::string& view_id,
                               int64 expected_content_size);
 
   // BrowserContextKeyedAPI implementation.