Implement asynchronous interface/plumbing for GetDefaultPrintSettings.

ppapi/api/dev/ppp_printing_dev.idl

 /* Copyright (c) 2012 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /**
  * Definition of the PPP_Printing interface.
  */
 
 // Note: This version should always match the PPB_Printing_Dev interface.
 label Chrome {
-  M21 = 0.6
+  M21 = 0.6,
+  M23 = 0.7

[raymes, 2012/07/20 22:46:56]

Trung mentioned that this interface version should always match the ppb
interface version. I'm not certain how to guarantee that though (just having the
label here doesn't guarantee the interface is generated)

[dmichael (off chromium), 2012/07/23 18:20:09]

I don't think that's strictly true...  your change would work fine either way.
But I think it's a practice that we wanted to start doing, even though it's
unnecessary a lot of the time.
There's a presubmit check to make sure that IDL changes are reflected in the
code (though it doesn't check that PPP and PPB interfaces match).

[raymes, 2012/07/24 00:37:08]

Done. I had to remove the M21 label for it to pick up the change. Backward
compatibility isn't needed on the PPP side by the looks of it.

On 2012/07/23 18:20:09, dmichael wrote:

 };
 
 /**
  * Specifies a contiguous range of page numbers to be printed.
  * The page numbers use a zero-based index.
  */
 [assert_size(8)]
 struct PP_PrintPageNumberRange_Dev {
   uint32_t first_page_number;
   uint32_t last_page_number;
@@ skipping 28 matching lines @@
 
   /** Ends the print session. Further calls to PrintPages will fail. */
   void End([in] PP_Instance instance);
 
   /**
    *  Returns true if the current content should be printed into the full page
    *  and not scaled down to fit within the printer's printable area.
    */
   PP_Bool IsScalingDisabled([in] PP_Instance instance);
 };