Add junit tests for //base/android

Adds a gyp and gn build target: base_junit_tests
Adds test suite: base_junit_tests

Depends on https://codereview.chromium.org/1048153002/
BUG=448030,472152

Review URL: https://codereview.chromium.org/1051343002

Cr-Commit-Position: refs/heads/master@{#326861}

base/BUILD.gn

@@ -1463,6 +1463,15 @@ if (is_android) {
     DEPRECATED_java_in_dir = "test/android/javatests/src"
   }
 
+  # GYP: //base.gyp:base_junit_tests
+  junit_binary("base_junit_tests") {
+    java_files = [ "android/junit/src/org/chromium/base/LogTest.java" ]
+    deps = [
+      ":base_java",
+      ":base_java_test_support",
+    ]
+  }
+
   # GYP: //base.gyp:base_java_application_state
   # GYP: //base.gyp:base_java_library_load_from_apk_status_codes
   # GYP: //base.gyp:base_java_library_process_type

base/android/junit/src/org/chromium/base/LogTest.java

+// 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 static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import org.chromium.testing.local.LocalRobolectricTestRunner;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.annotation.Config;
+import org.robolectric.annotation.Implementation;
+import org.robolectric.annotation.Implements;
+import org.robolectric.shadows.ShadowLog;
+
+import java.util.List;
+
+/** Unit tests for {@link Log}. */
+@RunWith(LocalRobolectricTestRunner.class)
+@Config(manifest = Config.NONE, shadows = {LogTest.PermissiveShadowLog.class})
+public class LogTest {
+    /** Test method for {@link Log#makeTag(String)} */
+    @Test
+    public void testMakeTag() {
+        assertEquals("chromium.Foo", Log.makeTag("Foo"));
+        assertEquals("chromium", Log.makeTag(null));
+        assertEquals("chromium", Log.makeTag(""));
+    }
+
+    /** Tests that the computed call origin is the correct one. */
+    @Test
+    public void callOriginTest() {
+        Log.d("Foo", "Bar");
+
+        List<ShadowLog.LogItem> logs = ShadowLog.getLogs();
+        assertEquals("Only one log should be written", 1, logs.size());
+
+        assertTrue("The origin of the log message (" + logs.get(0).msg + ") looks wrong.",
+                logs.get(0).msg.matches("\\[LogTest.java:\\d+\\].*"));
+    }
+
+    /** Tests that exceptions provided to the log functions are properly recognized and printed. */
+    @Test
+    public void exceptionLoggingTest() {
+        Throwable t = new Throwable() {
+            @Override
+            public String toString() {
+                return "MyThrowable";
+            }
+        };
+
+        Throwable t2 = new Throwable() {
+            @Override
+            public String toString() {
+                return "MyOtherThrowable";
+            }
+        };
+
+        List<ShadowLog.LogItem> logs = ShadowLog.getLogs();
+
+        // The throwable gets printed out
+        Log.i("Foo", "Bar", t);
+        assertEquals(t, logs.get(logs.size() - 1).throwable);
+        assertEquals("Bar", logs.get(logs.size() - 1).msg);
+
+        // The throwable can be both added to the message itself and printed out
+        Log.i("Foo", "Bar %s", t);
+        assertEquals(t, logs.get(logs.size() - 1).throwable);
+        assertEquals("Bar MyThrowable", logs.get(logs.size() - 1).msg);
+
+        // Non throwable are properly identified
+        Log.i("Foo", "Bar %s", t, "Baz");
+        assertNull(logs.get(logs.size() - 1).throwable);
+        assertEquals("Bar MyThrowable", logs.get(logs.size() - 1).msg);
+
+        // The last throwable is the one used that is going to be printed out
+        Log.i("Foo", "Bar %s %s", t, t2);
+        assertEquals(t2, logs.get(logs.size() - 1).throwable);
+        assertEquals("Bar MyThrowable MyOtherThrowable", logs.get(logs.size() - 1).msg);
+    }
+
+    /** Needed to allow debug/verbose logging that is disabled by default. */
+    @Implements(android.util.Log.class)
+    public static class PermissiveShadowLog extends ShadowLog {
+        @Implementation
+        public static boolean isLoggable(String tag, int level) {
+            return true;
+        }
+    }
+}

base/base.gyp

@@ -1500,6 +1500,23 @@
           },
           'includes': [ '../build/java.gypi' ],
         },
+        {
+          # GN: //base:base_junit_tests
+          'target_name': 'base_junit_tests',
+          'type': 'none',
+          'dependencies': [
+            'base_java',
+            'base_java_test_support',
+            '../testing/android/junit/junit_test.gyp:junit_test_support',
+          ],
+          'variables': {
+             'main_class': 'org.chromium.testing.local.JunitTestMain',
+             'src_paths': [
+               '../base/android/junit/',
+             ],
+           },
+          'includes': [ '../build/host_jar.gypi' ],
+        },
         {
           # GN: //base:base_javatests
           'target_name': 'base_javatests',