Move Start/EndPage() from NewPage/PageDone() to inside the metafile.

chrome/renderer/print_web_view_helper_win.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/renderer/print_web_view_helper.h"
 
 #include "base/logging.h"
 #include "base/process_util.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/render_messages_params.h"
@@ skipping 190 matching lines @@
   GetPageSizeAndMarginsInPoints(frame, page_number, params,
       &content_width_in_points, &content_height_in_points, NULL, NULL, NULL,
       NULL);
 
   // Since WebKit extends the page width depending on the magical scale factor
   // we make sure the canvas covers the worst case scenario (x2.0 currently).
   // PrintContext will then set the correct clipping region.
   int width = static_cast<int>(content_width_in_points * params.max_shrink);
   int height = static_cast<int>(content_height_in_points * params.max_shrink);
 
+  DCHECK((*metafile)->StartPage());

[vandebo (ex-Chrome), 2011/03/15 20:41:39]

Better to do bool foo = action; DCHECK(foo);

[dpapad, 2011/03/15 20:56:44]

Done.

+
 #if 0
   // TODO(maruel): This code is kept for testing until the 100% GDI drawing
   // code is stable. maruels use this code's output as a reference when the
   // GDI drawing code fails.
 
   // Mix of Skia and GDI based.
   skia::PlatformCanvas canvas(width, height, true);
   canvas.drawARGB(255, 255, 255, 255, SkXfermode::kSrc_Mode);
   float webkit_scale_factor = frame->printPage(page_number, &canvas);
   if (*scale_factor <= 0 || webkit_scale_factor <= 0) {
@@ skipping 26 matching lines @@
   float webkit_scale_factor = frame->printPage(page_number, &canvas);
   if (*scale_factor <= 0 || webkit_scale_factor <= 0) {
     NOTREACHED() << "Printing page " << page_number << " failed.";
   } else {
     // Update the dpi adjustment with the "page |scale_factor|" calculated in
     // webkit.
     *scale_factor /= webkit_scale_factor;
   }
 #endif
 
+  DCHECK((*metafile)->EndPage());
   skia::VectorPlatformDevice* platform_device =
       static_cast<skia::VectorPlatformDevice*>(canvas.getDevice());
   if (platform_device->alpha_blend_used() && !params.supports_alpha_blend) {
     // Close the device context to retrieve the compiled metafile.
     if (!(*metafile)->CloseDc())
       NOTREACHED();
 
     scoped_ptr<printing::NativeMetafile> metafile2(
         printing::NativeMetafileFactory::CreateMetafile());
     // Page used alpha blend, but printer doesn't support it.  Rewrite the
@@ skipping 58 matching lines @@
   // Copy the bits into shared memory.
   if (!metafile->GetData(shared_buf.memory(), buf_size)) {
     NOTREACHED() << "GetData() failed";
     shared_buf.Unmap();
     return false;
   }
   shared_buf.GiveToProcess(base::GetCurrentProcessHandle(), shared_mem_handle);
   shared_buf.Unmap();
   return true;
 }