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

chrome/browser/ui/tab_helpers.h

Index: chrome/browser/ui/tab_helpers.h
diff --git a/chrome/browser/ui/tab_helpers.h b/chrome/browser/ui/tab_helpers.h
index 1c678f2b55a08b530b7c09e7db86c4f0b2ee0b15..805e61108c77511c8962d4d6424f4ebba346ee86 100644
--- a/chrome/browser/ui/tab_helpers.h
+++ b/chrome/browser/ui/tab_helpers.h
@@ -21,6 +21,8 @@ namespace prerender {
 class PrerenderContents;
 }
 
+class HiddenWebContents;

[Vitaly Buka (NO REVIEWS), 2015/07/13 07:00:30]

don't need this

+
 // A "tab contents" is a WebContents that is used as a tab in a browser window
 // (or the equivalent on Android). The TabHelpers class allows specific classes
 // to attach the set of tab helpers that is used for tab contents.
@@ -50,6 +52,10 @@ class TabHelpers {
   // the full set of tab helpers to deal with it.
   friend class prerender::PrerenderContents;
 
+  // The hidden print preview needs to generate print previews, which is
+  // supported by tab helpers.
+  friend class HiddenPrintPreview;
+
   // Adopts the specified WebContents as a full-fledged browser tab, attaching
   // all the associated tab helpers that are needed for the WebContents to
   // serve in that role. It is safe to call this on a WebContents that was