Implement window.print() on Android

chrome/browser/printing/print_job_worker.h

Index: chrome/browser/printing/print_job_worker.h
diff --git a/chrome/browser/printing/print_job_worker.h b/chrome/browser/printing/print_job_worker.h
index a8378bb2353de2cd98746c087bfb5e02a595bba6..4a8442638fb9d21cd987591f41a14ada2eb1dc1e 100644
--- a/chrome/browser/printing/print_job_worker.h
+++ b/chrome/browser/printing/print_job_worker.h
@@ -9,6 +9,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread.h"
+#include "chrome/browser/printing/printer_query.h"
 #include "content/public/browser/browser_thread.h"
 #include "printing/page_number.h"
 #include "printing/print_job_constants.h"
@@ -39,10 +40,13 @@ class PrintJobWorker {
 
   void SetNewOwner(PrintJobWorkerOwner* new_owner);
 
-  // Initializes the print settings. If |ask_user_for_settings| is true, a
-  // Print... dialog box will be shown to ask the user his preference.
+  // Initializes the print settings. If |ask_settings_type| is ASK_USER, a
+  // Print... dialog box will be shown by the browser to ask the user his
+  // preference. If it is SYSTEM_SPECIFIC, showing that dialog box will be
+  // delegated to the system. It's used for script printing on android
+  // (see https://codereview.chromium.org/740983002/)
   void GetSettings(
-      bool ask_user_for_settings,
+      PrinterQuery::GetSettingsAskParam ask_settings_type,
       int document_page_count,
       bool has_selection,
       MarginType margin_type);
@@ -115,6 +119,9 @@ class PrintJobWorker {
   // back into the IO thread for GetSettingsDone().
   void GetSettingsWithUIDone(PrintingContext::Result result);
 
+  // Called on the UI thread to ask the system to show a print dialog.
+  void ShowSystemDialog();
+
   // Called on the UI thread to update the print settings.
   void UpdatePrintSettings(scoped_ptr<base::DictionaryValue> new_settings);