Bug 1485151 - Part 1 - Import StrictModeContext from Chromium. r=jchen,mhoye

Differential Revision: https://phabricator.services.mozilla.com/D4888

--HG--
extra : source : 424fcd7c1bef5f9591d749555c042c184cfbf313
extra : histedit_source : 614bd7bac33d7312079337aed2184b1e47d04418

mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/StrictModeContext.java

@@ -0,0 +1,87 @@
+// Copyright 2017 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.
+//
+// Copied from Chromium's /src/base/android/java/src/org/chromium/base/StrictModeContext.java.
+
+package org.mozilla.gecko.util;
+
+import android.os.StrictMode;
+
+import java.io.Closeable;
+
+/**
+ * Enables try-with-resources compatible StrictMode violation whitelisting.
+ *
+ * Example:
+ * <pre>
+ *     try (StrictModeContext unused = StrictModeContext.allowDiskWrites()) {
+ *         return Example.doThingThatRequiresDiskWrites();
+ *     }
+ * </pre>
+ *
+ */
+public final class StrictModeContext implements Closeable {
+    private final StrictMode.ThreadPolicy mThreadPolicy;
+    private final StrictMode.VmPolicy mVmPolicy;
+
+    private StrictModeContext(StrictMode.ThreadPolicy threadPolicy, StrictMode.VmPolicy vmPolicy) {
+        mThreadPolicy = threadPolicy;
+        mVmPolicy = vmPolicy;
+    }
+
+    private StrictModeContext(StrictMode.ThreadPolicy threadPolicy) {
+        this(threadPolicy, null);
+    }
+
+    private StrictModeContext(StrictMode.VmPolicy vmPolicy) {
+        this(null, vmPolicy);
+    }
+
+    /**
+     * Convenience method for disabling all VM-level StrictMode checks with try-with-resources.
+     * Includes everything listed here:
+     *     https://developer.android.com/reference/android/os/StrictMode.VmPolicy.Builder.html
+     */
+    public static StrictModeContext allowAllVmPolicies() {
+        StrictMode.VmPolicy oldPolicy = StrictMode.getVmPolicy();
+        StrictMode.setVmPolicy(StrictMode.VmPolicy.LAX);
+        return new StrictModeContext(oldPolicy);
+    }
+
+    /**
+     * Convenience method for disabling StrictMode for disk-writes with try-with-resources.
+     */
+    public static StrictModeContext allowDiskWrites() {
+        StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskWrites();
+        return new StrictModeContext(oldPolicy);
+    }
+
+    /**
+     * Convenience method for disabling StrictMode for disk-reads with try-with-resources.
+     */
+    public static StrictModeContext allowDiskReads() {
+        StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
+        return new StrictModeContext(oldPolicy);
+    }
+
+    /**
+     * Convenience method for disabling StrictMode for slow calls with try-with-resources.
+     */
+    public static StrictModeContext allowSlowCalls() {
+        StrictMode.ThreadPolicy oldPolicy = StrictMode.getThreadPolicy();
+        StrictMode.setThreadPolicy(
+                new StrictMode.ThreadPolicy.Builder(oldPolicy).permitCustomSlowCalls().build());
+        return new StrictModeContext(oldPolicy);
+    }
+
+    @Override
+    public void close() {
+        if (mThreadPolicy != null) {
+            StrictMode.setThreadPolicy(mThreadPolicy);
+        }
+        if (mVmPolicy != null) {
+            StrictMode.setVmPolicy(mVmPolicy);
+        }
+    }
+}

toolkit/content/license.html

@@ -2832,6 +2832,7 @@ WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #endif
         <li><code>browser/extensions/mortar/host/common/opengles2-utils.jsm</code></li>
         <li><code>editor/libeditor/EditorEventListener.cpp</code></li>
+        <li><code>mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/StrictModeContext.java</code></li>
         <li><code>security/sandbox/</code></li>
         <li><code>widget/cocoa/GfxInfo.mm</code></li>
     </ul>