Introduce ManifestUpgradeDetector for WebAPK to detect web manifest changes.

chrome/browser/android/webapk/manifest_upgrade_detector.cc

Index: chrome/browser/android/webapk/manifest_upgrade_detector.cc
diff --git a/chrome/browser/android/webapk/manifest_upgrade_detector.cc b/chrome/browser/android/webapk/manifest_upgrade_detector.cc
new file mode 100644
index 0000000000000000000000000000000000000000..58a3a86a2b678df53f17726b5d43d4bf9dc535bb
--- /dev/null
+++ b/chrome/browser/android/webapk/manifest_upgrade_detector.cc
@@ -0,0 +1,142 @@
+// Copyright 2016 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/webapk/manifest_upgrade_detector.h"
+
+#include <jni.h>
+
+#include "base/android/jni_string.h"
+#include "chrome/browser/android/shortcut_info.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/common/manifest.h"
+#include "jni/ManifestUpgradeDetector_jni.h"
+#include "url/gurl.h"
+
+namespace {
+
+// Returns whether the given |url| is within the scope of the |scope| url.
+bool IsInScope(const GURL& url, const GURL& scope) {
+  return base::StartsWith(url.spec(), scope.spec(),
+                         base::CompareCase::SENSITIVE);
+}
+
+}  // anonymous namespace
+
+jlong Initialize(JNIEnv* env,
+                 const JavaParamRef<jobject>& obj,
+                 const JavaParamRef<jobject>& java_web_contents,
+                 const JavaParamRef<jstring>& java_scope_url,
+                 const JavaParamRef<jstring>& java_web_manifest_url) {
+  content::WebContents* web_contents =
+      content::WebContents::FromJavaWebContents(java_web_contents);
+  GURL scope(base::android::ConvertJavaStringToUTF8(env, java_scope_url));
+  GURL web_manifest_url(base::android::ConvertJavaStringToUTF8(
+      env, java_web_manifest_url));
+  ManifestUpgradeDetector* manifest_upgrade_detector =
+      new ManifestUpgradeDetector(env, obj, web_contents, scope,
+                                  web_manifest_url);
+  return reinterpret_cast<intptr_t>(manifest_upgrade_detector);
+}
+
+ManifestUpgradeDetector::ManifestUpgradeDetector(
+    JNIEnv* env,
+    jobject obj,
+    content::WebContents* web_contents,
+    const GURL& scope,
+    const GURL& web_manifest_url)
+    : content::WebContentsObserver(web_contents),
+      started_(false),
+      scope_(scope),
+      web_manifest_url_(web_manifest_url),
+      weak_ptr_factory_(this) {
+  java_ref_.Reset(env, obj);
+}
+
+ManifestUpgradeDetector::~ManifestUpgradeDetector() {
+}
+
+// static
+bool ManifestUpgradeDetector::Register(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+void ManifestUpgradeDetector::ReplaceWebContents(
+    JNIEnv* env,
+    const JavaParamRef<jobject>& obj,
+    const JavaParamRef<jobject>& jweb_contents) {
+  content::WebContents* web_contents =
+      content::WebContents::FromJavaWebContents(jweb_contents);
+  content::WebContentsObserver::Observe(web_contents);
+}
+
+void ManifestUpgradeDetector::Destroy(JNIEnv* env,
+                                      const JavaParamRef<jobject>& obj) {
+  delete this;
+}
+
+void ManifestUpgradeDetector::Start(JNIEnv* env,
+                                    const JavaParamRef<jobject>& obj) {
+  started_ = true;
+}
+
+void ManifestUpgradeDetector::DidFinishLoad(
+    content::RenderFrameHost* render_frame_host,
+    const GURL& validated_url) {
+  if (render_frame_host->GetParent())
+    return;
+  if (!started_ || !IsInScope(validated_url, scope_))
+    return;
+
+  web_contents()->GetManifest(
+      base::Bind(&ManifestUpgradeDetector::OnDidGetManifest,
+                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void ManifestUpgradeDetector::OnDidGetManifest(
+    const GURL& manifest_url,
+    const content::Manifest& manifest) {
+  // If the manifest is empty, it means the current WebContents doesn't
+  // associate with a Web Manifest. In such case, we ignore the empty manifest
+  // and continue observing the WebContents's loading until we find a page that
+  // links to the Web Manifest that we are looking for.
+  // If the manifest URL is different from the current one, we will continue
+  // observing too. It is based on our assumption that it is invalid for
+  // web developers to change the Web Manifest location. When it does
+  // change, we will treat the new Web Manifest as the one of another WebAPK.
+  if (manifest.IsEmpty() || web_manifest_url_ != manifest_url)
+    return;
+
+  started_ = false;
+
+  ShortcutInfo info(GURL::EmptyGURL());
+  info.UpdateFromManifest(manifest);
+  info.manifest_url = manifest_url;
+
+  OnDataAvailable(info);
+}
+
+void ManifestUpgradeDetector::OnDataAvailable(const ShortcutInfo& info) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+
+  ScopedJavaLocalRef<jstring> java_url =
+      base::android::ConvertUTF8ToJavaString(env, info.url.spec());
+  ScopedJavaLocalRef<jstring> java_scope =
+      base::android::ConvertUTF8ToJavaString(env, info.scope.spec());
+  ScopedJavaLocalRef<jstring> java_name =
+      base::android::ConvertUTF16ToJavaString(env, info.name);
+  ScopedJavaLocalRef<jstring> java_short_name =
+      base::android::ConvertUTF16ToJavaString(env, info.short_name);
+
+  Java_ManifestUpgradeDetector_onDataAvailable(
+      env, java_ref_.obj(),
+      java_url.obj(),
+      java_scope.obj(),
+      java_name.obj(),
+      java_short_name.obj(),
+      info.display,
+      info.orientation,
+      info.theme_color,
+      info.background_color);
+}