[DevUI DFM] Add API and backend to install and load the DFM.

This CL adds DevUiModuleProvider classes (Java and C++) as backend to
install and load the DevUI DFM. The C++ API must be called from the UI
thread. It consists of query helpers:
* DevUiModuleProvider::GetInstance().ModuleInstalled(),
* DevUiModuleProvider::GetInstance().ModuleLoaded(),
and asynchronous (i.e., takes callbacks) actions:
* DevUiModuleProvider::GetInstance().InstallModule(),
* DevUiModuleProvider::GetInstance().LoadModule().

The Java backend handles DFM installation, and implements standard
on-demand DFM installation flow. For simplicity, no Java UI elements
(e.g., using Toast or InfoBar) as used. Instead, an interstitial page
that calls the C++ API will be used.

Some sources of complexity, also encountered by VrModuleProvider (upon
which the code is based) are:
* Interaction between C++ and Java DevUiModuleProvider via JNI calls
  and interaction between the singletons.
* Queue management for InstallModule() and LoadModule(), to handle the
  corner case of multiple concurrent install / load requests.

Bug: 927131
Change-Id: I4a6f3e4209857542a63e49ff79871a50bc5da4ab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1769170
Commit-Queue: Samuel Huang <huangs@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#692087}

chrome/android/BUILD.gn

@@ -10,6 +10,7 @@ import("//build/util/process_version.gni")
 import("//build/util/version.gni")
 import("//chrome/android/chrome_common_shared_library.gni")
 import("//chrome/android/chrome_public_apk_tmpl.gni")
+import("//chrome/android/features/dev_ui/dev_ui_module.gni")
 import("//chrome/android/features/tab_ui/buildflags.gni")
 import("//chrome/android/features/tab_ui/tab_management_java_sources.gni")
 import("//chrome/android/features/vr/public_vr_java_sources.gni")
@@ -530,6 +531,10 @@ java_group("chrome_all_java") {
   if (disable_tab_ui_dfm) {
     deps += [ "//chrome/android/features/tab_ui:java" ]
   }
+
+  if (dfmify_dev_ui) {
+    deps += [ "//chrome/android/modules/dev_ui/provider:java" ]
+  }
 }
 
 # This is a list of all base module jni headers. New features should add their
@@ -1110,20 +1115,20 @@ android_resources("chrome_public_apk_resources") {
 }
 
 version_resource_dir = "$target_gen_dir/templates/chrome_version_xml/res"
-verson_resource_file = "$version_resource_dir/values/strings.xml"
+version_resource_file = "$version_resource_dir/values/strings.xml"
 process_version("version_xml") {
   process_only = true
   template_file = "java/version_strings.xml.template"
   sources = [
     "//chrome/VERSION",
   ]
-  output = verson_resource_file
+  output = version_resource_file
 }
 
 android_resources("product_version_resources") {
   resource_dirs = []
   generated_resource_dirs = [ version_resource_dir ]
-  generated_resource_files = [ verson_resource_file ]
+  generated_resource_files = [ version_resource_file ]
   custom_package = "org.chromium.base"
   deps = [
     ":version_xml",

chrome/android/features/dev_ui/BUILD.gn

@@ -14,12 +14,11 @@ buildflag_header("buildflags") {
 }
 
 android_library("java") {
-  java_files =
-      [ "java/src/org/chromium/chrome/browser/dev_ui/DevUiModuleProvider.java" ]
-
   deps = [
     "//base:base_java",
+    "//chrome/android/features/dev_ui/public:java",
   ]
+  java_files = [ "java/src/org/chromium/chrome/features/dev_ui/DevUiImpl.java" ]
 }
 
 android_assets("pak_assets") {

chrome/android/features/dev_ui/dev_ui_module.gni

@@ -3,7 +3,8 @@
 # found in the LICENSE file.
 
 declare_args() {
-  # Whether Developer UI (chrome:// pages) should be split into a separate DFM.
+  # Whether Developer UI (chrome:// pages) should be split into a separate
+  # Dynamic Feature Module (DFM: //docs/android_dynamic_feature_modules.md).
   dfmify_dev_ui = false
 }
 

chrome/android/features/dev_ui/java/AndroidManifest.xml

@@ -13,5 +13,5 @@
         <dist:fusing dist:include="false" />
     </dist:module>
 
-    <application></application>
+    <application />
 </manifest>

chrome/android/features/dev_ui/java/src/org/chromium/chrome/browser/dev_ui/DevUiModuleProvider.java → chrome/android/features/dev_ui/java/src/org/chromium/chrome/features/dev_ui/DevUiImpl.java

@@ -2,13 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-package org.chromium.chrome.browser.dev_ui;
+package org.chromium.chrome.features.dev_ui;
 
 import org.chromium.base.annotations.UsedByReflection;
 
-/**
- * Provider for the Developer UI DFM. Currently this is a placeholder that serves as a kludge, so
- * Java code exists somewhere.
- */
-@UsedByReflection("DevUiModuleProvider.java")
-public interface DevUiModuleProvider {}
+/** Implementation for the DevUI DFM. */
+@UsedByReflection("DevUiModule")
+public class DevUiImpl implements DevUi {}

chrome/android/features/dev_ui/public/BUILD.gn

+# 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.
+
+import("//build/config/android/rules.gni")
+
+android_library("java") {
+  deps = [
+    "//base:base_java",
+    "//components/module_installer/android:module_installer_java",
+    "//components/module_installer/android:module_interface_java",
+  ]
+  java_files = [ "java/src/org/chromium/chrome/features/dev_ui/DevUi.java" ]
+
+  # Need this to generate DevUiModule.java.
+  annotation_processor_deps =
+      [ "//components/module_installer/android:module_interface_processor" ]
+}

chrome/android/features/dev_ui/public/DEPS

+include_rules = [
+  "+components/module_installer",
+]

chrome/android/features/dev_ui/public/java/src/org/chromium/chrome/features/dev_ui/DevUi.java

+// 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.
+
+package org.chromium.chrome.features.dev_ui;
+
+import org.chromium.components.module_installer.ModuleInterface;
+
+/** Interface to call into DevUI feature. */
+@ModuleInterface(module = "dev_ui", impl = "org.chromium.chrome.features.dev_ui.DevUiImpl")
+public interface DevUi {}

chrome/android/modules/dev_ui/provider/BUILD.gn

+# 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.
+
+import("//build/config/android/rules.gni")
+
+android_library("java") {
+  deps = [
+    "//base:base_java",
+    "//chrome/android/features/dev_ui/public:java",
+    "//components/module_installer/android:module_installer_java",
+  ]
+  java_files = [
+    "java/src/org/chromium/chrome/features/dev_ui/DevUiModuleProvider.java",
+  ]
+}
+
+generate_jni("jni_headers") {
+  sources = [
+    "java/src/org/chromium/chrome/features/dev_ui/DevUiModuleProvider.java",
+  ]
+}

chrome/android/modules/dev_ui/provider/java/src/org/chromium/chrome/features/dev_ui/DevUiModuleProvider.java

+// 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.
+
+package org.chromium.chrome.features.dev_ui;
+
+import org.chromium.base.Log;
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.JNINamespace;
+import org.chromium.base.annotations.UsedByReflection;
+
+/** Helpers for DevUI DFM installation. */
+@JNINamespace("dev_ui")
+@UsedByReflection("DevUiModuleProvider")
+public class DevUiModuleProvider {
+    private static final String TAG = "DEV_UI";
+
+    private long mNativeDevUiModuleProvider;
+
+    @CalledByNative
+    private DevUiModuleProvider(long nativeDevUiModuleProvider) {
+        mNativeDevUiModuleProvider = nativeDevUiModuleProvider;
+    }
+
+    @CalledByNative
+    private static boolean isModuleInstalled() {
+        return DevUiModule.isInstalled();
+    }
+
+    @CalledByNative
+    private void installModule() {
+        DevUiModule.install((success) -> {
+            Log.i(TAG, "Install status: %s", success);
+            if (mNativeDevUiModuleProvider != 0) {
+                nativeOnInstallResult(mNativeDevUiModuleProvider, success);
+            }
+        });
+    }
+
+    @CalledByNative
+    private void onNativeDestroy() {
+        mNativeDevUiModuleProvider = 0;
+    }
+
+    private native void nativeOnInstallResult(long nativeDevUiModuleProvider, boolean success);
+}

chrome/browser/BUILD.gn

@@ -2941,6 +2941,14 @@ jumbo_split_static_library("browser") {
       ]
       deps += [ "//chrome/browser/supervised_user/supervised_user_error_page" ]
     }
+
+    if (dfmify_dev_ui) {
+      sources += [
+        "android/dev_ui/dev_ui_module_provider.cc",
+        "android/dev_ui/dev_ui_module_provider.h",
+      ]
+      deps += [ "//chrome/android/modules/dev_ui/provider:jni_headers" ]
+    }
   } else {  # !is_android
     sources += [
       "accessibility/invert_bubble_prefs.cc",

chrome/browser/DEPS

@@ -132,6 +132,7 @@ include_rules = [
   "+components/mirroring/browser",
   "+components/mirroring/mojom",
   "+components/mirroring/service",
+  "+components/module_installer/android",
   "+components/nacl/broker",
   "+components/nacl/browser",
   "+components/nacl/common",

chrome/browser/android/dev_ui/DEPS

+include_rules = [
+  "+chrome/android/modules/dev_ui/provider/jni_headers",
+]

chrome/browser/android/dev_ui/dev_ui_module_provider.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 "chrome/browser/android/dev_ui/dev_ui_module_provider.h"
+
+#include <memory>
+#include <utility>
+
+#include "base/logging.h"
+#include "base/task/post_task.h"
+#include "chrome/android/modules/dev_ui/provider/jni_headers/DevUiModuleProvider_jni.h"
+#include "chrome/browser/android/dfm_resource_bundle_helper.h"
+
+namespace dev_ui {
+
+namespace {
+
+constexpr base::TaskTraits kWorkerTaskTraits = {
+    base::ThreadPool(), base::MayBlock(), base::TaskPriority::USER_BLOCKING,
+    base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN};
+
+}  // namespace
+
+// static
+DevUiModuleProvider& DevUiModuleProvider::GetInstance() {
+  static base::NoDestructor<DevUiModuleProvider> instance;
+  return *instance;
+}
+
+bool DevUiModuleProvider::ModuleInstalled() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  return Java_DevUiModuleProvider_isModuleInstalled(
+      base::android::AttachCurrentThread());
+}
+
+bool DevUiModuleProvider::ModuleLoaded() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  return DevUiModuleProvider::GetInstance().is_loaded_;
+}
+
+void DevUiModuleProvider::InstallModule(
+    base::OnceCallback<void(bool)> on_finished) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  // Also use the call's side effect of ensuring that split compat is loaded.
+  // TODO(tiborg): Once ModuleInstalled() is made more light-weight, add
+  // explicit split compat loading code here.
+  if (ModuleInstalled()) {
+    std::move(on_finished).Run(true);
+    return;
+  }
+  on_attempted_install_callbacks_.push(std::move(on_finished));
+  // Don't request DevUI module multiple times in parallel.
+  if (on_attempted_install_callbacks_.size() > 1)
+    return;
+
+  // This should always return, since there is no InfoBar UI to retry (thus
+  // avoiding crbug.com/996925 and crbug.com/996959).
+  Java_DevUiModuleProvider_installModule(base::android::AttachCurrentThread(),
+                                         j_dev_ui_module_provider_);
+}
+
+// Called by Java.
+void DevUiModuleProvider::OnInstallResult(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj,
+    bool success) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  DCHECK_GT(on_attempted_install_callbacks_.size(), 0UL);
+  while (!on_attempted_install_callbacks_.empty()) {
+    std::move(on_attempted_install_callbacks_.front()).Run(success);
+    on_attempted_install_callbacks_.pop();
+  }
+}
+
+void DevUiModuleProvider::LoadModule(base::OnceCallback<void()> on_loaded) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  if (ModuleLoaded()) {
+    std::move(on_loaded).Run();
+    return;
+  }
+  on_loaded_callbacks_.push(std::move(on_loaded));
+  // Don't load multiple times in parallel.
+  if (on_loaded_callbacks_.size() > 1)
+    return;
+  // android::LoadDevUiResources() is assumed to always succeed.
+  base::PostTaskAndReply(FROM_HERE, kWorkerTaskTraits,
+                         base::BindOnce(&android::LoadDevUiResources),
+                         base::BindOnce(&DevUiModuleProvider::OnLoadedModule,
+                                        base::Unretained(this)));
+}
+
+DevUiModuleProvider::DevUiModuleProvider()
+    : j_dev_ui_module_provider_(Java_DevUiModuleProvider_Constructor(
+          base::android::AttachCurrentThread(),
+          reinterpret_cast<jlong>(this))) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+}
+
+DevUiModuleProvider::~DevUiModuleProvider() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  Java_DevUiModuleProvider_onNativeDestroy(base::android::AttachCurrentThread(),
+                                           j_dev_ui_module_provider_);
+}
+
+void DevUiModuleProvider::OnLoadedModule() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  is_loaded_ = true;
+  DCHECK_GT(on_loaded_callbacks_.size(), 0UL);
+  while (!on_loaded_callbacks_.empty()) {
+    std::move(on_loaded_callbacks_.front()).Run();
+    on_loaded_callbacks_.pop();
+  }
+}
+
+}  // namespace dev_ui

chrome/browser/android/dev_ui/dev_ui_module_provider.h

+// 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.
+
+#ifndef CHROME_BROWSER_ANDROID_DEV_UI_DEV_UI_MODULE_PROVIDER_H_
+#define CHROME_BROWSER_ANDROID_DEV_UI_DEV_UI_MODULE_PROVIDER_H_
+
+#include <jni.h>
+#include <queue>
+
+#include "base/android/jni_android.h"
+#include "base/callback.h"
+#include "base/no_destructor.h"
+#include "base/sequence_checker.h"
+
+namespace dev_ui {
+
+class DevUiModuleProvider {
+ public:
+  static DevUiModuleProvider& GetInstance();
+
+  // Returns true if the DevUI module is installed.
+  bool ModuleInstalled();
+
+  // Returns true if the DevUI module is installed and loaded.
+  bool ModuleLoaded();
+
+  // Asynchronously requests to install the DevUI module. |on_finished| is
+  // called after the module install is completed, and takes a bool to indicate
+  // whether module install is successful.
+  void InstallModule(base::OnceCallback<void(bool)> on_finished);
+
+  // Called by Java.
+  void OnInstallResult(JNIEnv* env,
+                       const base::android::JavaParamRef<jobject>& obj,
+                       bool success);
+
+  // Assuming that the DevUI module is installed, asynchronously loads DevUI
+  // resources.
+  void LoadModule(base::OnceCallback<void()> on_loaded);
+
+ private:
+  friend base::NoDestructor<DevUiModuleProvider>;
+  DevUiModuleProvider();
+  ~DevUiModuleProvider();
+  DevUiModuleProvider(const DevUiModuleProvider&) = delete;
+  void operator=(const DevUiModuleProvider&) = delete;
+
+  // Callback for LoadModule().
+  void OnLoadedModule();
+
+  base::android::ScopedJavaGlobalRef<jobject> j_dev_ui_module_provider_;
+
+  // Queue of InstallModule() callbacks.
+  std::queue<base::OnceCallback<void(bool)>> on_attempted_install_callbacks_;
+
+  // Queue of LoadModule() callbacks.
+  std::queue<base::OnceCallback<void()>> on_loaded_callbacks_;
+
+  // Source of truth for ModuleLoaded(), updated when LoadModule() succeeds.
+  bool is_loaded_ = false;
+
+  SEQUENCE_CHECKER(sequence_checker_);
+};
+
+}  // namespace dev_ui
+
+#endif  // CHROME_BROWSER_ANDROID_DEV_UI_DEV_UI_MODULE_PROVIDER_H_

chrome/chrome_paks.gni

@@ -209,7 +209,7 @@ template("chrome_extra_paks") {
 # * resources.pak
 # * locale .pak files
 #
-# Paramters:
+# Parameters:
 #   output_dir [required]: Directory to output .pak files. Locale .pak files
 #       will always be place in $output_dir/locales
 #   additional_extra_paks: List of extra .pak sources for resources.pak.