ABANDONED: OOPIFs: Moving stitching of local paths from renderer to browser process.

content/public/renderer/render_frame.h

Index: content/public/renderer/render_frame.h
diff --git a/content/public/renderer/render_frame.h b/content/public/renderer/render_frame.h
index 335c2234416af8ce9cc851c4274ef07eea26b823..95a86d8223e38f3abd3576982bce30aae415afb3 100644
--- a/content/public/renderer/render_frame.h
+++ b/content/public/renderer/render_frame.h
@@ -57,6 +57,7 @@ class CONTENT_EXPORT RenderFrame : public IPC::Listener,
                                    public IPC::Sender {
  public:
   // Returns the RenderFrame given a WebFrame.
+  static const RenderFrame* FromWebFrame(const blink::WebFrame* web_frame);

[ncarter (slow), 2015/10/08 20:57:55]

I appreciate the justification you gave for adding these const overrides in the
CL description, but for reasons I'll explain below, we shouldn't need them. The
TL;DR is that "const RenderFrame*" ought to be useless.

The rules we try to enforce for the content api (which this, being
content/public, is part of) are posted here:
http://www.chromium.org/developers/content-module/content-api. One of them says:
"Don't add the const identifier to interfaces. ... For interfaces implemented by
content, the implementation details doesn't have to be exposed."  Per that
policy, all the methods of RenderFrame ought to be non-const, and it's common
for RenderFrame's const-hostility to spilling over to code that has to interacts
with it. Although there are a couple const methods today, they're in violation
of the policy and we'd like to eradicate them too.

Yes, this goes against the Effective C++ recommendation of "use const wherever
possible", but doing so is a conscious decision.

As an alternative, I think we can either make the existing FromWebFrame method
accept a const WebFrame and return a non-const RenderFrame (using the const_cast
code you already added), or else just make the callers provide a non-const
WebFrame. 

[Łukasz Anforowicz, 2015/10/09 16:54:08]

Done:

- Removed const-related changes

- Added a GetRoutingIdForFrameOrProxy overload that takes
  a const WebFrame* (with a comment stating why const_cast
  there is safe).

   static RenderFrame* FromWebFrame(blink::WebFrame* web_frame);
 
   // Returns the RenderFrame given a routing id.
@@ -66,7 +67,7 @@ class CONTENT_EXPORT RenderFrame : public IPC::Listener,
   virtual RenderView* GetRenderView() = 0;
 
   // Get the routing ID of the frame.
-  virtual int GetRoutingID() = 0;
+  virtual int GetRoutingID() const = 0;

[ncarter (slow), 2015/10/08 20:57:55]

Per the above, const methods in the content/public interfaces are forbidden.

[Łukasz Anforowicz, 2015/10/09 16:54:08]

Done.

 
   // Returns the associated WebFrame.
   virtual blink::WebLocalFrame* GetWebFrame() = 0;