Revert "[mojo][bindings] Move Router exception to executor thread"

This reverts commit 279dbf78.

Reason for revert: investigating a proper solution for https://crbug.com/1120959 might take a while

Original change's description:
> [mojo][bindings] Move Router exception to executor thread
> 
> This change moves throwing the exception if Router was not closed to the
> executor thread to make it crash instead of just logging.
> 
> Bug: 1087098
> Change-Id: I65c510bdbadedc3a0589807843c57e925c0351c5
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2321345
> Reviewed-by: Bo <boliu@chromium.org>
> Commit-Queue: Oksana Zhuravlova <oksamyt@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#800765}

TBR=boliu@chromium.org,oksamyt@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1087098
Change-Id: Iabeda9f10d9fcffd9d9894b72506a55b43907455
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2378897Reviewed-by: Oksana Zhuravlova <oksamyt@chromium.org>
Commit-Queue: Oksana Zhuravlova <oksamyt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#802068}

mojo/public/java/bindings/src/org/chromium/mojo/bindings/AutoCloseableRouter.java

@@ -114,12 +114,11 @@ class AutoCloseableRouter implements Router {
                 @Override
                 public void run() {
                     close();
-                    throw new IllegalStateException(
-                            "Warning: Router objects should be explicitly closed "
-                                    + "when no longer required otherwise you may leak handles.",
-                            mAllocationException);
                 }
             });
+            throw new IllegalStateException("Warning: Router objects should be explicitly closed "
+                            + "when no longer required otherwise you may leak handles.",
+                    mAllocationException);
         }
         super.finalize();
     }