Add support for TraceEvent before the native library is loaded.

base/android/javatests/src/org/chromium/base/EarlyTraceEventTest.java

Index: base/android/javatests/src/org/chromium/base/EarlyTraceEventTest.java
diff --git a/base/android/javatests/src/org/chromium/base/EarlyTraceEventTest.java b/base/android/javatests/src/org/chromium/base/EarlyTraceEventTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..a547a0d51e671844816fee921a6a2265c7a19c8f
--- /dev/null
+++ b/base/android/javatests/src/org/chromium/base/EarlyTraceEventTest.java
@@ -0,0 +1,110 @@
+// 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.base;
+
+import android.os.Process;
+import android.test.InstrumentationTestCase;
+import android.test.suitebuilder.annotation.SmallTest;
+
+import org.chromium.base.test.util.Feature;
+
+/**
+ * Tests for {@link org.chromium.base.EarlyTraceEvent}.
+ */
+public class EarlyTraceEventTest extends InstrumentationTestCase {
+    @Override
+    public void tearDown() {
+        EarlyTraceEvent.disable();
+    }
+
+    @SmallTest
+    @Feature({"Android-AppBase"})
+    public void testIsDisabledByDefault() {
+        assertFalse(EarlyTraceEvent.isEnabled());
+    }
+
+    @SmallTest
+    @Feature({"Android-AppBase"})
+    public void testCanBeEnabled() {
+        EarlyTraceEvent.enable();
+        assertTrue(EarlyTraceEvent.isEnabled());
+    }
+
+    @SmallTest
+    @Feature({"Android-AppBase"})
+    public void testCanRecordEvent() {
+        EarlyTraceEvent.enable();
+        long threadId = Process.myTid();
+        EarlyTraceEvent.begin("MyEvent", "");
+        EarlyTraceEvent.end("MyEvent", "");
+        EarlyTraceEvent.EarlyTraceEventsNativeReader reader = EarlyTraceEvent.getAll();
+        String[] names = reader.readNames();
+        assertEquals(names.length, 1);
+        assertEquals(names[0], "MyEvent");
+        long[] threadIds = reader.readThreadIds();
+        assertEquals(threadIds.length, 1);
+        assertEquals(threadIds[0], threadId);
+    }
+
+    @SmallTest
+    @Feature({"Android-AppBase"})
+    public void testNoEvents() {
+        EarlyTraceEvent.enable();
+        EarlyTraceEvent.EarlyTraceEventsNativeReader reader = EarlyTraceEvent.getAll();
+        assertEquals(reader.readNames().length, 0);
+    }
+
+    @SmallTest
+    @Feature({"Android-AppBase"})
+    public void testNoNestedSameNameEvents() {
+        EarlyTraceEvent.enable();
+        EarlyTraceEvent.begin("MyEvent", "");
+        try {
+            EarlyTraceEvent.begin("MyEvent", "");
+        } catch (IllegalArgumentException e) {
+            // Expected
+            return;
+        }
+        assertFalse(true);
+    }
+
+    @SmallTest
+    @Feature({"Android-AppBase"})
+    public void testSeveralEvents() {
+        EarlyTraceEvent.enable();
+        EarlyTraceEvent.begin("FirstEvent", "");
+        EarlyTraceEvent.begin("SecondEvent", "");
+        EarlyTraceEvent.end("FirstEvent", "");
+        Thread thread = new Thread(new Runnable(){
+                @Override
+                public void run() {
+                    EarlyTraceEvent.end("SecondEvent", "");
+                }});
+        thread.run();
+        try {
+            thread.join();
+        } catch (InterruptedException e) {
+            // Too bad
+        }
+
+        EarlyTraceEvent.EarlyTraceEventsNativeReader reader = EarlyTraceEvent.getAll();
+        assertEquals(reader.readNames().length, 2);
+        assertEquals(reader.readNames()[0], "FirstEvent");
+        assertEquals(reader.readNames()[1], "SecondEvent");
+    }
+
+    @SmallTest
+    @Feature({"Android-AppBase"})
+    public void testEventsPending() {
+        EarlyTraceEvent.enable();
+        EarlyTraceEvent.begin("FirstEvent", "");
+        EarlyTraceEvent.begin("SecondEvent", "");
+        EarlyTraceEvent.end("FirstEvent", "");
+
+        EarlyTraceEvent.EarlyTraceEventsNativeReader reader = EarlyTraceEvent.getAll();
+        assertEquals(reader.readNames().length, 1);
+        assertEquals(reader.readNames()[0], "FirstEvent");
+    }
+}