Add a "Simplify Page" option to the print preview dialog

chrome/browser/ui/webui/print_preview/print_preview_handler.cc

Index: chrome/browser/ui/webui/print_preview/print_preview_handler.cc
diff --git a/chrome/browser/ui/webui/print_preview/print_preview_handler.cc b/chrome/browser/ui/webui/print_preview/print_preview_handler.cc
index d9c40280300d4b92ec9d6a684095c25b5f160db2..cfce61e261277ef4965b49ad94693ab7af30a75d 100644
--- a/chrome/browser/ui/webui/print_preview/print_preview_handler.cc
+++ b/chrome/browser/ui/webui/print_preview/print_preview_handler.cc
@@ -30,6 +30,7 @@
 #include "base/values.h"
 #include "chrome/browser/app_mode/app_mode_utils.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/dom_distiller/tab_utils.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/printing/print_dialog_cloud.h"
 #include "chrome/browser/printing/print_error_dialog.h"
@@ -57,6 +58,8 @@
 #include "components/cloud_devices/common/cloud_device_description.h"
 #include "components/cloud_devices/common/cloud_devices_urls.h"
 #include "components/cloud_devices/common/printer_description.h"
+#include "components/dom_distiller/content/distillable_page_utils.h"
+#include "components/dom_distiller/core/url_utils.h"
 #include "components/printing/common/print_messages.h"
 #include "components/signin/core/browser/gaia_cookie_manager_service.h"
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
@@ -839,8 +842,20 @@ void PrintPreviewHandler::HandleGetPreview(const base::ListValue* args) {
   }
 
   VLOG(1) << "Print preview request start";
-  RenderViewHost* rvh = initiator->GetRenderViewHost();
-  rvh->Send(new PrintMsg_PrintPreview(rvh->GetRoutingID(), *settings));
+
+  bool print_friendly = false;
+  if (!settings->GetBoolean(printing::kSettingPrintFriendlyEnabled,
+                            &print_friendly)) {
+    NOTREACHED();
+  }
+
+  if (print_friendly) {
+    hidden_print_preview_.reset(
+      new HiddenPrintPreview(initiator, print_preview_ui(), settings.Pass()));
+  } else {
+    RenderViewHost* rvh = initiator->GetRenderViewHost();
+    rvh->Send(new PrintMsg_PrintPreview(rvh->GetRoutingID(), *settings));
+  }
 }
 
 void PrintPreviewHandler::HandlePrint(const base::ListValue* args) {
@@ -1256,6 +1271,21 @@ void PrintPreviewHandler::SendInitialSettings(
   if (print_preview_ui()->source_is_modifiable())
     GetNumberFormatAndMeasurementSystem(&initial_settings);
   web_ui()->CallJavascriptFunction("setInitialSettings", initial_settings);
+
+  WebContents* initiator = GetInitiator();
+  if (initiator && cmdline->HasSwitch(switches::kEnableDomDistiller) &&
+      dom_distiller::url_utils::IsUrlDistillable(
+            initiator->GetLastCommittedURL())) {
+    dom_distiller::IsDistillablePage(initiator, false,

[Vitaly Buka (NO REVIEWS), 2015/07/13 07:00:31]

I don't see guaranty that HandleIsPageDistillableResult will never be called
after PrintPreviewHandler is destroyed.
So you need weak_factory_.GetWeakPtr() insted of base::Unretained(this) 

+      base::Bind(&PrintPreviewHandler::HandleIsPageDistillableResult,
+                 base::Unretained(this)));
+  }
+}
+
+void PrintPreviewHandler::HandleIsPageDistillableResult(bool distillable) {
+  VLOG(1) << "Distillable page detection finished";
+  if (distillable)
+    web_ui()->CallJavascriptFunction("onDetectedSimplifiablePage");
 }
 
 void PrintPreviewHandler::ClosePreviewDialog() {