Revert "[Bundles] Add module_installer_backend.cc with native OnInstallModule handler."

This reverts commit 461a68da.

Reason for revert: This is no longer needed: We've decided to let each DFM load native resources (on install) in its own way, instead of relying on common infrastructure.

Reverting this also fixes crbug.com/994035

Original change's description:
> [Bundles] Add module_installer_backend.cc with native OnInstallModule handler.
>
> To prepare for handling native resource loading after DFM installation,
> this CL adds a new hook in ModuleInstallerBackend.onFinished() to call
> (via JNI) a new native handler for each newly installed module:
>   JNI_ModuleInstallerBackend_OnInstallModule()
>
> AsyncTask is used to make the JNI call asynchronous, taking place
> outside the UI thread. This allows file access (e.g., to open native
> resources) to take place in the native code, thereby preventing
> assert failure in Debug builds.
>
> After the JNI call, |mListener.onFinished()| is called on UI thread,
> just like before.
>
> Bug: 927131
> Change-Id: I36880cc7739a48534052b51d3d655d1ae0beb29a
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1702905
> Commit-Queue: Samuel Huang <huangs@chromium.org>
> Reviewed-by: Tibor Goldschwendt <tiborg@chromium.org>
> Reviewed-by: danakj <danakj@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#680452}

TBR=danakj@chromium.org,huangs@chromium.org,agrieve@chromium.org,tiborg@chromium.org

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

Bug: 927131,994035
Change-Id: If9fdbffb35d226615135c9db596ad50960bc2958
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1756154Reviewed-by: Samuel Huang <huangs@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#687309}

chrome/browser/BUILD.gn

@@ -2866,7 +2866,6 @@ jumbo_split_static_library("browser") {
       "//components/feed:feature_list",
       "//components/invalidation/impl:feature_list",
       "//components/language/android:language_bridge",
-      "//components/module_installer/android:module_installer",
       "//components/omnibox/browser",
       "//components/payments/content/android",
       "//components/resources:components_resources",

components/module_installer/android/BUILD.gn

@@ -58,22 +58,6 @@ android_library("module_installer_impl_java") {
   ]
 }
 
-generate_jni("module_installer_jni_headers") {
-  sources = [
-    "java/src-impl/org/chromium/components/module_installer/ModuleInstallerBackend.java",
-  ]
-}
-
-static_library("module_installer") {
-  sources = [
-    "module_installer_backend.cc",
-  ]
-  deps = [
-    ":module_installer_jni_headers",
-    "//base",
-  ]
-}
-
 android_library("module_installer_test_java") {
   testonly = true
   java_files = [ "javatests/src/org/chromium/components/module_installer/ModuleInstallerRule.java" ]

components/module_installer/android/DEPS

 include_rules = [
-  "+base",
   "+components/crash/android",
 ]

components/module_installer/android/java/src-impl/org/chromium/components/module_installer/ModuleInstallerBackend.java

@@ -5,13 +5,10 @@
 package org.chromium.components.module_installer;
 
 import org.chromium.base.ThreadUtils;
-import org.chromium.base.annotations.JNINamespace;
-import org.chromium.base.task.AsyncTask;
 
 import java.util.List;
 
 /** A backend for installing dynamic feature modules that contain the actual install logic. */
-@JNINamespace("module_installer")
 /* package */ abstract class ModuleInstallerBackend {
     private final OnFinishedListener mListener;
 
@@ -51,28 +48,6 @@ import java.util.List;
 
     /** To be called when module install has finished. */
     protected void onFinished(boolean success, List<String> moduleNames) {
-        ThreadUtils.assertOnUiThread();
-
-        // Call native to perform additional tasks (e.g., load resources). These
-        // tasks can be blocking, and are done asynchronously (outside the UI
-        // thread). Once done, return to call |mListender.onFinished()| on the
-        // UI thread.
-        // TODO(crbug.com/987252): Add timing metrics.
-        new AsyncTask<Void>() {
-            @Override
-            protected Void doInBackground() {
-                for (String moduleName : moduleNames) {
-                    nativeOnInstallModule(success, moduleName);
-                }
-                return null;
-            }
-
-            @Override
-            protected void onPostExecute(Void result) {
-                mListener.onFinished(success, moduleNames);
-            }
-        }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
+        mListener.onFinished(success, moduleNames);
     }
-
-    private static native void nativeOnInstallModule(boolean success, String moduleName);
 }

components/module_installer/android/module_installer_backend.cc

-// Copyright 2019 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "base/android/jni_android.h"
-#include "components/module_installer/android/module_installer_jni_headers/ModuleInstallerBackend_jni.h"
-
-namespace module_installer {
-
-// Handles native specific initialization in after module is installed. This may
-// be blocking, so the call should be done asynchronously.
-void JNI_ModuleInstallerBackend_OnInstallModule(
-    JNIEnv* env,
-    jboolean j_success,
-    const base::android::JavaParamRef<jstring>& j_module_name) {
-  // TODO(crbug.com/927131): Add code to detect DevUI DFM installation, and load
-  // the associated resource PAK file. This will require the following:
-  //   bool success = j_success;
-  //   (Needs #include "base/android/jni_string.h").
-  //   std::string module_name(ConvertJavaStringToUTF8(j_module_name));
-
-  // TODO(crbug.com/986960): Specialize this function to perform resource
-  // loading only. Required parameters can be injected to support data-driven
-  // flow. This will require massive refactoring first, however.
-}
-
-}  // namespace module_installer