Upstream oodles of Chrome for Android code into Chromium.

chrome/android/java_staging/src/org/chromium/chrome/browser/document/CipherKeyActivity.java

Index: chrome/android/java_staging/src/org/chromium/chrome/browser/document/CipherKeyActivity.java
diff --git a/chrome/android/java_staging/src/org/chromium/chrome/browser/document/CipherKeyActivity.java b/chrome/android/java_staging/src/org/chromium/chrome/browser/document/CipherKeyActivity.java
new file mode 100644
index 0000000000000000000000000000000000000000..0302290b385742054e392c1eecb70fcbee141889
--- /dev/null
+++ b/chrome/android/java_staging/src/org/chromium/chrome/browser/document/CipherKeyActivity.java
@@ -0,0 +1,74 @@
+// Copyright 2015 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.browser.document;
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.Intent;
+import android.os.Bundle;
+
+import org.chromium.content.browser.crypto.CipherFactory;
+
+/**
+ * An activity responsible for retaining the incognito cipher key for the duration of an incognito
+ * session. The activity gets brought forward for two reasons: to restore the cipher key before a
+ * new incognito window is launched or to save the current cipher key. If brought forward to
+ * restore, the activity is passed an intent and options to call after the restore process is
+ * complete. Otherwise the activity just puts itself in background causing onSaveInstanceState to
+ * get called and save the cipher keys to the activity's bundle.
+ */
+public class CipherKeyActivity extends Activity {
+
+    /**
+     * An intent name for specifying the next intent to invoke.
+     */
+    public static final String FORWARD_INTENT = "forward_intent";
+
+    /**
+     * An options Bundle to use with intent specified by "forward_intent".
+     */
+    public static final String FORWARD_OPTIONS = "forward_options";
+
+    /**
+     * Generates an intent to {@link CipherKeyActivity} to restore cipher keys from the bundle
+     * if possible.
+     * @param context The context to use.
+     * @param forwardIntent The intent cipher key activity will call when it's done.
+     * @param options The options to pass into startActivity call of the forward intent.
+     * @return The intent.
+     */
+    public static Intent createIntent(Context context, Intent forwardIntent, Bundle options) {
+        Intent intent = new Intent(context, CipherKeyActivity.class);
+        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+        if (forwardIntent != null) intent.putExtra(FORWARD_INTENT, forwardIntent);
+        if (options != null) intent.putExtra(FORWARD_OPTIONS, options);
+        return intent;
+    }
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        if (savedInstanceState != null) {
+            CipherFactory.getInstance().restoreFromBundle(savedInstanceState);
+        }
+        Intent nextIntent = (Intent) getIntent().getParcelableExtra(FORWARD_INTENT);
+        if (nextIntent != null) {
+            startActivity(nextIntent, (Bundle) getIntent().getParcelableExtra(FORWARD_OPTIONS));
+        }
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        moveTaskToBack(true);
+    }
+
+    @Override
+    protected void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        CipherFactory.getInstance().saveToBundle(outState);
+    }
+
+}