Auto merge of #526 - glennw:debug-opts, r=pcwalton

Add API for tweaking debug options.

Right now, it's possible to toggle the profiler. In the future
this can include options for subpixel AA, shader hot reload etc.

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Author: bors-servo

webrender/src/renderer.rs

@@ -1665,6 +1665,10 @@ impl Renderer {
         &mut self.debug
     }
 
+    pub fn get_profiler_enabled(&mut self) -> bool {
+        self.enable_profiler
+    }
+
     pub fn set_profiler_enabled(&mut self, enabled: bool) {
         self.enable_profiler = enabled;
     }