[android_webview] Make it possible to enable trace for the shell.

In r265466 we moved initTraceEvent to the glue layer. This makes
it impossible to trace from the test shell.

BUG=None

Review URL: https://codereview.chromium.org/265833005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@267546 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 27 insertions, 0 deletions

diff --git a/android_webview/test/shell/src/org/chromium/android_webview/shell/AwShellApplication.java b/android_webview/test/shell/src/org/chromium/android_webview/shell/AwShellApplication.java
index f6488f4..b019d8a 100644
--- a/android_webview/test/shell/src/org/chromium/android_webview/shell/AwShellApplication.java
+++ b/android_webview/test/shell/src/org/chromium/android_webview/shell/AwShellApplication.java
@@ -11,8 +11,12 @@ import android.util.Log;
 import org.chromium.android_webview.AwBrowserProcess;
 import org.chromium.base.BaseSwitches;
 import org.chromium.base.CommandLine;
+import org.chromium.base.TraceEvent;
 import org.chromium.content.browser.ResourceExtractor;
 
+/**
+ * The android_webview shell Application subclass.
+ */
 public class AwShellApplication extends Application {
 
     private static final String TAG = "AwShellApplication";
@@ -38,5 +42,10 @@ public class AwShellApplication extends Application {
         ResourceExtractor.setMandatoryPaksToExtract(MANDATORY_PAKS);
         ResourceExtractor.setExtractImplicitLocaleForTesting(false);
         AwBrowserProcess.loadLibrary();
+
+        if (CommandLine.getInstance().hasSwitch(AwShellSwitches.ENABLE_ATRACE)) {
+            Log.e(TAG, "Enabling Android trace.");
+            TraceEvent.setATraceEnabled(true);
+        }
     }
 }
diff --git a/android_webview/test/shell/src/org/chromium/android_webview/shell/AwShellSwitches.java b/android_webview/test/shell/src/org/chromium/android_webview/shell/AwShellSwitches.java
new file mode 100644
index 0000000..2aceb92
--- /dev/null
+++ b/android_webview/test/shell/src/org/chromium/android_webview/shell/AwShellSwitches.java
@@ -0,0 +1,18 @@
+// Copyright 2014 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.android_webview.shell;
+
+/**
+ * Contains all of the command line switches that are specific to the test shell of
+ * the android_webview glue layer.
+ */
+public abstract class AwShellSwitches {
+    // Enables Android systrace path for Chrome traces.
+    public static final String ENABLE_ATRACE = "enable-atrace";
+
+    // Prevent instantiation.
+    private AwShellSwitches() {}
+}
+