Send request to show print system dialog to Metro.

BUG=134256
TEST=Make sure there are no way to open the system's print dialog in Chrome when running in Metro. The print device charm should be shown instead.


Review URL: https://chromiumcodereview.appspot.com/10701155

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@146399 0039d316-1c4b-4281-b951-d872f2087c98

printing/printing_context_win.cc

@@ -14,6 +14,7 @@
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
+#include "base/win/metro.h"
 #include "printing/backend/win_helper.h"
 #include "printing/print_job_constants.h"
 #include "printing/print_settings_initializer_win.h"
@@ -219,6 +220,21 @@ void PrintingContextWin::AskUserForSettings(
     const PrintSettingsCallback& callback) {
 #if !defined(USE_AURA)
   DCHECK(!in_print_job_);
+
+  if (base::win::IsMetroProcess()) {
+    // The system dialog can not be opened while running in Metro.
+    // But we can programatically launch the Metro print device charm though.
+    HMODULE metro_module = base::win::GetMetroModule();
+    if (metro_module != NULL) {
+      typedef void (*MetroShowPrintUI)();
+      MetroShowPrintUI metro_show_print_ui =
+          reinterpret_cast<MetroShowPrintUI>(
+              ::GetProcAddress(metro_module, "MetroShowPrintUI"));
+      if (metro_show_print_ui)
+        metro_show_print_ui();
+    }
+    return callback.Run(CANCEL);
+  }
   dialog_box_dismissed_ = false;
 
   HWND window;