Return early in destroyModule if there is no module.

Bug: 924118
Change-Id: I19611361435e142e06440faa1a241c1a45dd76e5
Reviewed-on: https://chromium-review.googlesource.com/c/1433244Reviewed-by: Michael van Ouwerkerk <mvanouwerkerk@chromium.org>
Commit-Queue: Anna Malova <amalova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#625641}

chrome/android/java/src/org/chromium/chrome/browser/customtabs/dynamicmodule/ModuleLoader.java

@@ -233,7 +233,7 @@ public class ModuleLoader {
     }
 
     public void destroyModule(@DestructionReason int reason) {
-        assert mModuleEntryPoint != null;
+        if (mModuleEntryPoint == null) return;
 
         ModuleMetrics.recordDestruction(reason);
         mModuleEntryPoint.onDestroy();