Defer request to print a PDF when the user initiates the entire frame and the PDF hasn't loaded.

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 e4129eef490197b6e61ea78d3e06f191c558d3cd..9e40a06db37474ef7017e85c5c8c0491b09cf807 100644
--- a/chrome/renderer/printing/print_web_view_helper.cc
+++ b/chrome/renderer/printing/print_web_view_helper.cc
@@ -791,7 +791,8 @@ PrintWebViewHelper::PrintWebViewHelper(content::RenderView* render_view)
       print_node_in_progress_(false),
       is_loading_(false),
       is_scripted_preview_delayed_(false),
-      weak_ptr_factory_(this) {
+      weak_ptr_factory_(this),
+      on_stop_loading_type_(PRINT_PREVIEW_SCRIPTED) {
 }
 
 PrintWebViewHelper::~PrintWebViewHelper() {}
@@ -820,7 +821,18 @@ void PrintWebViewHelper::DidStartLoading() {
 
 void PrintWebViewHelper::DidStopLoading() {
   is_loading_ = false;
-  ShowScriptedPrintPreview();
+
+  // |on_stop_loading_type_| should be reset to the default value
+  // PRINT_PREVIEW_SCRIPTED after is its equal to
+  // PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME because the race condition has
+  // been handled.
+  if (on_stop_loading_type_ == PRINT_PREVIEW_SCRIPTED) {
+    ShowScriptedPrintPreview();
+  } else if (on_stop_loading_type_ ==
+             PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME) {
+    RequestPrintPreview(on_stop_loading_type_);
+    on_stop_loading_type_ = PRINT_PREVIEW_SCRIPTED;
+  }
 }
 
 // Prints |frame| which called window.print().
@@ -1725,6 +1737,14 @@ void PrintWebViewHelper::RequestPrintPreview(PrintPreviewRequestType type) {
       return;
     }
     case PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME: {

[ivandavid, 2014/08/13 20:58:55]

This is the only case where we should handle the race condition. Handling this
condition in PRINT_PREVIEW_USER_INITIATED_SELECTION will break sheets and
doesn't seem appropriate as the only problem was with
PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME.

[Vitaly Buka (NO REVIEWS), 2014/08/13 23:39:45]

No, it is not.

Try to 
1. open huge pdf (for example pdf reference)
2. before it finish loading, click PRINT icon in bottom right corner
3. It would get into PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE and open empty
preview



On 2014/08/13 20:58:55, ivandavid wrote:

[ivandavid, 2014/08/14 03:38:13]

Done.

[ivandavid, 2014/08/14 03:38:13]

Oh OK. I figured why the PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE code path was
causing sheets to not work. See the comment in ppb_pdf_impl.cc

+      // Handles case where this function has been called, but DidStopLoading()
+      // hasn't been called yet. RequestPrintPreview() will be called again, at
+      // the end of DidStopLoading() with the same value for |type|.
+      if (is_loading_ && GetPlugin(print_preview_context_.source_frame())) {
+        on_stop_loading_type_ = PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME;
+        return;
+      }
+
       break;
     }
     case PRINT_PREVIEW_USER_INITIATED_SELECTION: {