Move click-to-play to about:flags.

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 1be1f212d9b526f772247748fd08007e4e542001..bbc3f6861b093704e90e1ff49c2004945068e947 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -185,6 +185,13 @@ const Experiment kExperiments[] = {
     kOsAll,
     switches::kEnableSnapStart
   },
+  {
+    "click-to-play",   // Do not change; see above.
+    IDS_FLAGS_CLICK_TO_PLAY_NAME,
+    IDS_FLAGS_CLICK_TO_PLAY_DESCRIPTION,
+    kOsAll,
+    switches::kEnableClickToPlay
+  },
 };
 
 const Experiment* experiments = kExperiments;