Enable page selection for WebView printing

android_webview/renderer/aw_print_web_view_helper_delegate.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/renderer/aw_print_web_view_helper_delegate.h"
 
 #include "third_party/WebKit/public/web/WebElement.h"
 
 namespace android_webview {
 
 AwPrintWebViewHelperDelegate::~AwPrintWebViewHelperDelegate() {}
 
 bool AwPrintWebViewHelperDelegate::CancelPrerender(
     content::RenderFrame* render_frame) {
   return false;
 }
 
 blink::WebElement AwPrintWebViewHelperDelegate::GetPdfElement(
     blink::WebLocalFrame* frame) {
   return blink::WebElement();
 }
 
 bool AwPrintWebViewHelperDelegate::IsPrintPreviewEnabled() {
   return false;
 }
 
 bool AwPrintWebViewHelperDelegate::IsAskPrintSettingsEnabled() {
-  return false;
+  return true;

[sgurun-gerrit only, 2017/03/23 19:16:59]

two comments:

I think this is to enable browser asking print settings from user, or at least
that was the original intent in desktop, which does not apply to WebView. Can
you update the comment about showing UI in
https://cs.chromium.org/chromium/src/components/printing/renderer/print_web_v...

also the base class has  default implementation which  true, so you can now
remove this method altogether.

[Lei Zhang, 2017/03/23 19:35:18]

Yes, that was the original intent, but this is fine. The browser side code can
handle the "ask for settings" task however it likes. Better comments are
welcome.

[sgurun-gerrit only, 2017/03/23 19:38:18]

alright then, no worries about updating comment.

[Shimi Zhang, 2017/03/23 23:21:56]

Done.

 }
 
 bool AwPrintWebViewHelperDelegate::IsScriptedPrintEnabled() {
   return false;
 }
 
 bool AwPrintWebViewHelperDelegate::OverridePrint(blink::WebLocalFrame* frame) {
   return false;
 }
 
 }  // namespace android_webview