Revert of Fix for race condition where print preview hangs when attempting to...

Revert of Fix for race condition where print preview hangs when attempting to print a PDF that hasn't loaded. (https://codereview.chromium.org/427723004/)

Reason for revert:
The changes fix an issue, but cause a more serious one. 

crbug.com/402402

Original issue's description:
> Fix for race condition where print preview hangs when attempting to print a PDF that hasn't loaded.
> 
> If |type| in RequestPrintPreview() equals PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME and |is_loading_| is true, RequestPrintPreview() returns,
> then is called again, right after |is_loading_| is set to false in DidStopLoading(). 
> 
> 
> BUG=376969
> TEST=See bug for steps to reproduce.
> 
> Additional way to reproduce:
> Build blink_tests and browser_tests in out/Release. Then in src/webkit/tools/layout_tests run this command:
> ./run_webkit_tests.py --platform browser_test.linux source_pdf/
> 
> you can replace linux with win or mac depending on your platform.
> 
> The program will attempt to save a PDF as a PDF through print preview. It will eventually fail because Print Preview will hang due to this bug.
> If you want visual confirmation that this will happen open:
> src/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/browser_test_driver.py.
> 
> Then add this line of code to the function cmd_line.
> cmd.append('--enable-pixel-output-in-tests')
> 
> Then run the script again. Enabling pixel output will also make it significantly more likely for the bug to occur.
> Its also more likely to happen on windows for some reason.
> 
> This is how I came across the bug.
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=287982

Review URL: https://codereview.chromium.org/463123004

Cr-Commit-Position: refs/heads/master@{#289181}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@289181 0039d316-1c4b-4281-b951-d872f2087c98

chrome/renderer/printing/print_web_view_helper.cc

@@ -820,8 +820,7 @@ void PrintWebViewHelper::DidStartLoading() {
 
 void PrintWebViewHelper::DidStopLoading() {
   is_loading_ = false;
-  if (!on_stop_loading_closure_.is_null())
-    on_stop_loading_closure_.Run();
+  ShowScriptedPrintPreview();
 }
 
 // Prints |frame| which called window.print().
@@ -1712,9 +1711,6 @@ void PrintWebViewHelper::RequestPrintPreview(PrintPreviewRequestType type) {
         // Wait for DidStopLoading. Plugins may not know the correct
         // |is_modifiable| value until they are fully loaded, which occurs when
         // DidStopLoading() is called. Defer showing the preview until then.
-        on_stop_loading_closure_ =
-            base::Bind(&PrintWebViewHelper::ShowScriptedPrintPreview,
-                       base::Unretained(this));
       } else {
         base::MessageLoop::current()->PostTask(
             FROM_HERE,
@@ -1729,17 +1725,6 @@ void PrintWebViewHelper::RequestPrintPreview(PrintPreviewRequestType type) {
       return;
     }
     case PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME: {
-      // Wait for DidStopLoading. Continuing with this function while
-      // |is_loading_| is true will cause print preview to hang when try to
-      // print a PDF document.
-      if (is_loading_ && GetPlugin(print_preview_context_.source_frame())) {
-        on_stop_loading_closure_ =
-            base::Bind(&PrintWebViewHelper::RequestPrintPreview,
-                       base::Unretained(this),
-                       type);
-        return;
-      }
-
       break;
     }
     case PRINT_PREVIEW_USER_INITIATED_SELECTION: {
@@ -1748,15 +1733,6 @@ void PrintWebViewHelper::RequestPrintPreview(PrintPreviewRequestType type) {
       break;
     }
     case PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE: {
-      // Same situation as in PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME.
-      if (is_loading_ && GetPlugin(print_preview_context_.source_frame())) {
-        on_stop_loading_closure_ =
-            base::Bind(&PrintWebViewHelper::RequestPrintPreview,
-                       base::Unretained(this),
-                       type);
-        return;
-      }
-
       params.webnode_only = true;
       break;
     }

chrome/renderer/printing/print_web_view_helper.h

@@ -7,7 +7,6 @@
 
 #include <vector>
 
-#include "base/callback.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/shared_memory.h"
@@ -462,12 +461,6 @@ class PrintWebViewHelper
   bool is_loading_;
   bool is_scripted_preview_delayed_;
   base::WeakPtrFactory<PrintWebViewHelper> weak_ptr_factory_;
-
-  // Used to fix a race condition where the source is a PDF and print preview
-  // hangs because RequestPrintPreview is called before DidStopLoading() is
-  // called. This is a store for the RequestPrintPreview() call and its
-  // parameters so that it can be invoked after DidStopLoading.
-  base::Closure on_stop_loading_closure_;
   DISALLOW_COPY_AND_ASSIGN(PrintWebViewHelper);
 };