[Android] Remove createHandleObserver(View view)

There is no usage of this version anywhere, so removing it.

Bug: 805531
Change-Id: I11d1fe29268ae17255d05d79283dca9d7a83bcc2
Reviewed-on: https://chromium-review.googlesource.com/959302Reviewed-by: Bo <boliu@chromium.org>
Commit-Queue: Shimi Zhang <ctzsm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542563}

content/public/android/java/src/org/chromium/content/browser/ContentClassFactory.java

@@ -4,8 +4,6 @@
 
 package org.chromium.content.browser;
 
-import android.view.View;
-
 import org.chromium.base.ThreadUtils;
 import org.chromium.content.browser.selection.SelectionInsertionHandleObserver;
 import org.chromium.content.browser.selection.SelectionPopupControllerImpl;
@@ -48,13 +46,4 @@ public class ContentClassFactory {
         // Implemented by a subclass.
         return null;
     }
-
-    /**
-     * Creates HandleObserver object.
-     */
-    // TODO(ctzsm): Remove this overload after we removed all usage of it.
-    public SelectionInsertionHandleObserver createHandleObserver(View view) {
-        // Implemented by a subclass.
-        return null;
-    }
 }