Implement window.print() on Android

chrome/renderer/printing/print_web_view_helper.cc

Index: chrome/renderer/printing/print_web_view_helper.cc
diff --git a/chrome/renderer/printing/print_web_view_helper.cc b/chrome/renderer/printing/print_web_view_helper.cc
index bb1ab8fadee51109c7bd115befface4d35b677da..d51cbffd9df36510bdd2584d6a9d72bef661fe09 100644
--- a/chrome/renderer/printing/print_web_view_helper.cc
+++ b/chrome/renderer/printing/print_web_view_helper.cc
@@ -795,9 +795,6 @@ void PrintWebViewHelper::DisablePreview() {
 
 bool PrintWebViewHelper::IsScriptInitiatedPrintAllowed(
     blink::WebFrame* frame, bool user_initiated) {
-#if defined(OS_ANDROID)
-  return false;
-#endif  // defined(OS_ANDROID)
   // If preview is enabled, then the print dialog is tab modal, and the user
   // can always close the tab on a mis-behaving page (the system print dialog
   // is app modal). If the print was initiated through user action, don't
@@ -822,6 +819,9 @@ void PrintWebViewHelper::DidStopLoading() {
 // Prints |frame| which called window.print().
 void PrintWebViewHelper::PrintPage(blink::WebLocalFrame* frame,
                                    bool user_initiated) {
+
+  DLOG(INFO) << "DGN PrintPage - From Script - routing_id: " << routing_id();
+
   DCHECK(frame);
 
   // Allow Prerendering to cancel this print request if necessary.
@@ -831,11 +831,19 @@ void PrintWebViewHelper::PrintPage(blink::WebLocalFrame* frame,
     return;
   }
 
-  if (!IsScriptInitiatedPrintAllowed(frame, user_initiated))
+  if (!IsScriptInitiatedPrintAllowed(frame, user_initiated)) {
+    DLOG(INFO) << "DGN PrintPage - Script printing not allowed";
     return;
+  }
 
   if (!g_is_preview_enabled_) {
-    Print(frame, blink::WebNode());

[dgn, 2014/11/25 17:07:42]

past that point, it I didn't find any way of knowing if I'm coming from a script
or not, since both the js and the UI initiated prints go through Print() and
OnScriptedPrint()

+    bool use_system_specific_flow = false;
+
+#if defined(OS_ANDROID)
+    use_system_specific_flow = true;
+#endif
+
+    Print(frame, blink::WebNode(), use_system_specific_flow);
   } else {
     print_preview_context_.InitWithFrame(frame);
     RequestPrintPreview(PRINT_PREVIEW_SCRIPTED);
@@ -947,6 +955,7 @@ bool PrintWebViewHelper::GetPrintFrame(blink::WebLocalFrame** frame) {
 
 #if defined(ENABLE_BASIC_PRINTING)
 void PrintWebViewHelper::OnPrintPages() {
+  DLOG(INFO) << "DGN - OnPrintPages - Call from PrintManager";
   blink::WebLocalFrame* frame;
   if (GetPrintFrame(&frame))
     Print(frame, blink::WebNode());
@@ -1243,10 +1252,15 @@ void PrintWebViewHelper::PrintNode(const blink::WebNode& node) {
 }
 
 void PrintWebViewHelper::Print(blink::WebLocalFrame* frame,
-                               const blink::WebNode& node) {
+                               const blink::WebNode& node,
+                               const bool use_system_specific_flow) {
   // If still not finished with earlier print request simply ignore.
-  if (prep_frame_view_)
+  DLOG(INFO) << "DGN Print";
+
+  if (prep_frame_view_) {
+    DLOG(INFO) << "DGN Print request ignored";
     return;
+  }
 
   FrameReference frame_ref(frame);
 
@@ -1256,6 +1270,8 @@ void PrintWebViewHelper::Print(blink::WebLocalFrame* frame,
     return;  // Failed to init print page settings.
   }
 
+  DLOG(INFO) << "DGN CalculateNumberOfPages OK";
+
   // Some full screen plugins can say they don't want to print.
   if (!expected_page_count) {
     DidFinishPrinting(FAIL_PRINT);
@@ -1264,11 +1280,14 @@ void PrintWebViewHelper::Print(blink::WebLocalFrame* frame,
 
   // Ask the browser to show UI to retrieve the final print settings.
   if (!GetPrintSettingsFromUser(frame_ref.GetFrame(), node,
-                                expected_page_count)) {
+                                expected_page_count,
+                                use_system_specific_flow)) {
     DidFinishPrinting(OK);  // Release resources and fail silently.
     return;
   }
 
+  DLOG(INFO) << "DGN GetPrintSettingsFromUser OK";
+
   // Render Pages for printing.
   if (!RenderPagesForPrint(frame_ref.GetFrame(), node)) {
     LOG(ERROR) << "RenderPagesForPrint failed";
@@ -1278,6 +1297,9 @@ void PrintWebViewHelper::Print(blink::WebLocalFrame* frame,
 }
 
 void PrintWebViewHelper::DidFinishPrinting(PrintingResult result) {
+  if (result == OK) DLOG(INFO) << "DGN DidFinishPrinting";
+  else DLOG(INFO) << "DGN DidFinishPrinting - Failure: " << result;
+
   switch (result) {
     case OK:
       break;
@@ -1541,7 +1563,8 @@ bool PrintWebViewHelper::UpdatePrintSettings(
 
 bool PrintWebViewHelper::GetPrintSettingsFromUser(blink::WebFrame* frame,
                                                   const blink::WebNode& node,
-                                                  int expected_pages_count) {
+                                                  int expected_pages_count,
+                                                  const bool system_specific) {
   PrintHostMsg_ScriptedPrint_Params params;
   PrintMsg_PrintPages_Params print_settings;
 
@@ -1552,6 +1575,7 @@ bool PrintWebViewHelper::GetPrintSettingsFromUser(blink::WebFrame* frame,
   if (PrintingNodeOrPdfFrame(frame, node))
     margin_type = GetMarginsForPdf(frame, node);
   params.margin_type = margin_type;
+  params.use_system_specific_flow = system_specific;
 
   Send(new PrintHostMsg_DidShowPrintDialog(routing_id()));
 
@@ -1574,6 +1598,7 @@ bool PrintWebViewHelper::RenderPagesForPrint(blink::WebLocalFrame* frame,
                                              const blink::WebNode& node) {
   if (!frame || prep_frame_view_)
     return false;
+
   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
   const PrintMsg_Print_Params& print_params = params.params;
   prep_frame_view_.reset(new PrepareFrameAndViewForPrint(