Add CommandLineArgumentParameter and use it for WebView tests

base/test/android/javatests/src/org/chromium/base/test/util/parameter/parameters/CommandLineArgumentParameter.java

Index: base/test/android/javatests/src/org/chromium/base/test/util/parameter/parameters/CommandLineArgumentParameter.java
diff --git a/base/test/android/javatests/src/org/chromium/base/test/util/parameter/parameters/CommandLineArgumentParameter.java b/base/test/android/javatests/src/org/chromium/base/test/util/parameter/parameters/CommandLineArgumentParameter.java
new file mode 100644
index 0000000000000000000000000000000000000000..6c73ece2b9eb3d7602d0c363acbdbf08440a171e
--- /dev/null
+++ b/base/test/android/javatests/src/org/chromium/base/test/util/parameter/parameters/CommandLineArgumentParameter.java
@@ -0,0 +1,42 @@
+// 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.test.util.parameter.parameters;
+
+import org.chromium.base.test.util.parameter.BaseParameter;
+import org.chromium.base.test.util.parameter.Parameter;
+
+/**
+ * Instructs the test runner to execute the test with modified command-line flags.
+ * Flags to add are specified using 'stringArray' of argument named 'add',
+ * and flags to remove -- in the argument named 'remove'. A parameter without arguments
+ * instructs to run the test with default command-line flags.
+ *
+ * Example:
+ * @ParameterizedTest.Set(tests = {
+ *             @ParameterizedTest(parameters = {
+ *                         @Parameter(
+ *                                 tag = CommandLineArgumentParameter.PARAMETER_TAG)}),
+ *             @ParameterizedTest(parameters = {
+ *                         @Parameter(
+ *                                 tag = CommandLineArgumentParameter.PARAMETER_TAG,
+ *                                 arguments = {
+ *                                     @Parameter.Argument(
+ *                                         name = CommandLineArgumentParameter.ADD_ARG,
+ *                                         stringArray = {'--arg1', '--arg2'})
+ *             })})})
+ *
+ * Note that because the entire instrumentation test process needs to be restarted to apply
+ * modified command-line arguments, this annotation is handled by test_runner.py, not by
+ * BaseTestResult class.
+ */
+public class CommandLineArgumentParameter extends BaseParameter {

[jbudorick, 2015/10/27 16:14:36]

I'm not crazy about having both this and @CommandLineFlags.Add/Remove. Maybe we
could merge them somehow...

[mnaganov (inactive), 2015/10/27 23:53:30]

I thought about that, but what I disliked is wordiness of ParameterizedTest
syntax, so instead of:

@CommandLineFlags.Add(ChromeSwitches.ENABLE_APP_INSTALL_ALERTS)

we will now have:

@ParameterizedTest(parameters = {
  @Parameter(
    tag = CommandLineArgumentParameter.PARAMETER_TAG,
      arguments = {
        @Parameter.Argument(
          name = CommandLineArgumentParameter.ADD_ARG, stringArray =
{ChromeSwitches.ENABLE_APP_INSTALL_ALERTS})
})})})

Kind of gross, isn't it?

So I would reserve ParameterizedTest for the cases where we actually need to
alternate flags. 

[jbudorick, 2015/10/28 16:36:35]

Yeah, that's pretty nasty.

What about something like

public class CommandLineFlags {
  @interface Add
  @interface Remove
  public class Parameter extends BaseParameter {
    ...
  }

}

?

That way the flags are all handled in one place, but we retain the simple
@CommandLineFlags.Add case.

+    public static final String PARAMETER_TAG = "cmdlinearg-parameter";
+    public static final String ADD_ARG = "add";
+    public static final String REMOVE_ARG = "remove";
+
+    public CommandLineArgumentParameter(Parameter.Reader parameterReader) {
+        super(PARAMETER_TAG, parameterReader);
+    }
+}