Add support for distilling current WebContents

chrome/browser/ui/tab_helpers.cc

Index: chrome/browser/ui/tab_helpers.cc
diff --git a/chrome/browser/ui/tab_helpers.cc b/chrome/browser/ui/tab_helpers.cc
index 05924e3767b77f4e4895d89d4a3ee6383fd11f32..5bdbb2f5a39d135717d3055a0315fd10d97b6dfd 100644
--- a/chrome/browser/ui/tab_helpers.cc
+++ b/chrome/browser/ui/tab_helpers.cc
@@ -29,6 +29,7 @@
 #include "chrome/common/chrome_switches.h"
 #include "components/autofill/content/browser/content_autofill_driver.h"
 #include "components/autofill/core/browser/autofill_manager.h"
+#include "components/dom_distiller/content/web_contents_main_frame_observer.h"
 #include "components/password_manager/core/browser/password_manager.h"
 #include "content/public/browser/web_contents.h"
 #include "extensions/browser/view_type_utils.h"
@@ -191,6 +192,12 @@ void TabHelpers::AttachTabHelpers(WebContents* web_contents) {
 #endif  // defined(ENABLE_FULL_PRINTING)
 #endif  // defined(ENABLE_PRINTING) && !defined(OS_ANDROID)
 
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableDomDistiller)) {
+    dom_distiller::WebContentsMainFrameObserver::CreateForWebContents(
+        web_contents);
+  }
+
 #if defined(ENABLE_ONE_CLICK_SIGNIN)
   // If this is not an incognito window, setup to handle one-click login.
   // We don't want to check that the profile is already connected at this time