Remove deprecated method - obtainSurfaceScope(<no args>)

As part of a three sided change, remove the old version
of the API now that it is no longer in use.

Bug: 1080884
Change-Id: If344fbbedadad6c5c807baad3443a3811860cdf2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2199981Reviewed-by: Justin DeWitt <dewittj@chromium.org>
Commit-Queue: Peter Williamson <petewil@chromium.org>
Cr-Commit-Position: refs/heads/master@{#772046}

chrome/browser/xsurface/android/java/src/org/chromium/chrome/browser/xsurface/ProcessScope.java

@@ -19,14 +19,6 @@ public interface ProcessScope {
      */
     default void resetAccount() {}
 
-    /**
-     * Deprecated - Will remove once the other overload is in use.
-     **/
-    @Nullable
-    default SurfaceScope obtainSurfaceScope() {
-        return null;
-    }
-
     /**
      * Returns a SurfaceScope which should be one per Surface. That Surface can have multiple
      * HybridListRenderers and SurfaceRenderers within its UI.
@@ -35,6 +27,6 @@ public interface ProcessScope {
      **/
     @Nullable
     default SurfaceScope obtainSurfaceScope(Context activityContext) {
-        return obtainSurfaceScope();
+        return null;
     }
 }