Ensure pdf plugin sends DidStartLoading() consistently

pdf/instance.cc

Index: pdf/instance.cc
diff --git a/pdf/instance.cc b/pdf/instance.cc
index 9dee0f6aaeca5f3b2ff101085ac9a8f92e2ac5bb..2c38585f81996bf04436725dc41bb708b1c1bb7b 100644
--- a/pdf/instance.cc
+++ b/pdf/instance.cc
@@ -349,6 +349,10 @@ bool Instance::Init(uint32_t argc, const char* argn[], const char* argv[]) {
     // For PDFs embedded in a frame, we don't get the data automatically like we
     // do for full-frame loads.  Start loading the data manually.
     LoadUrl(url);
+  } else {
+    DCHECK(!did_call_start_loading_);

[Vitaly Buka (NO REVIEWS), 2014/07/16 18:32:45]

Maybe CHECK() to make crash in release, so we could see reports

+    pp::PDF::DidStartLoading(this);
+    did_call_start_loading_ = true;

[jam, 2014/07/16 21:25:43]

I'm a bit confused, I tried doing window.print() (per the code being edited in
the other file). I hit line 348 twice in the renderer for print preview, but
both times the full_ was false. how is this else statement being reached?

   }
 
   ZoomLimitsChanged(kMinZoom, kMaxZoom);