Allow extensions to specify that they are not allowed in incognito mode.

extensions/common/manifest_handlers/incognito_manifest_unittest.cc

+// 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.
+
+#include "extensions/browser/extension_util.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/manifest_test.h"
+
+namespace extensions {
+
+using IncognitoManifestTest = ManifestTest;
+
+TEST_F(IncognitoManifestTest, IncognitoNotAllowed) {
+  scoped_refptr<Extension> extension(
+      LoadAndExpectSuccess("incognito_not_allowed.json"));

[not at google - send to devlin, 2015/09/18 21:49:20]

actually can you also make assertions about the IncognitoInfo here? I know that
CanBeIncognitoEnabled is what you're going for at the end of the day, but there
are other methods/properties to test, namely everything public on
https://codereview.chromium.org/1351223003/diff/40001/extensions/common/manif...
(so I'd expect to see assertions for IsSplitMode and IsIncognitoAllowed here).

(we could go further - there are other untested things - but this is far enough)

[Not at Google. Contact bengr, 2015/09/18 22:07:33]

Done.

+  EXPECT_FALSE(util::CanBeIncognitoEnabled(extension.get()));
+}
+
+TEST_F(IncognitoManifestTest, IncognitoSpanning) {
+  scoped_refptr<Extension> extension(
+      LoadAndExpectSuccess("incognito_spanning.json"));
+  EXPECT_TRUE(util::CanBeIncognitoEnabled(extension.get()));
+}
+
+TEST_F(IncognitoManifestTest, IncognitoSplit) {
+  scoped_refptr<Extension> extension(
+      LoadAndExpectSuccess("incognito_split.json"));
+  EXPECT_TRUE(util::CanBeIncognitoEnabled(extension.get()));
+}
+
+TEST_F(IncognitoManifestTest, IncognitoUnspecified) {
+  scoped_refptr<Extension> extension(LoadAndExpectSuccess("minimal.json"));
+  EXPECT_TRUE(util::CanBeIncognitoEnabled(extension.get()));
+}
+
+}  // namespace extensions