Generalize ExtensionIconSet to store icon paths for custom size sets

chrome/common/extensions/manifest_tests/extension_manifests_icon_unittest.cc

Index: chrome/common/extensions/manifest_tests/extension_manifests_icon_unittest.cc
diff --git a/chrome/common/extensions/manifest_tests/extension_manifests_icon_unittest.cc b/chrome/common/extensions/manifest_tests/extension_manifests_icon_unittest.cc
index 23c05fde7da8407951f04a6c32f30a319bf5aff5..5637dd43121a9a1c0da20992440d37c9fd8beec1 100644
--- a/chrome/common/extensions/manifest_tests/extension_manifests_icon_unittest.cc
+++ b/chrome/common/extensions/manifest_tests/extension_manifests_icon_unittest.cc
@@ -20,9 +20,8 @@ TEST_F(ExtensionManifestTest, NormalizeIconPaths) {
 TEST_F(ExtensionManifestTest, InvalidIconSizes) {
   scoped_refptr<extensions::Extension> extension(
       LoadAndExpectSuccess("init_ignored_icon_size.json"));
-  EXPECT_EQ("", extension->icons().Get(
-      static_cast<ExtensionIconSet::Icons>(300),
-      ExtensionIconSet::MATCH_EXACTLY));
+  EXPECT_EQ("",
+            extension->icons().Get(300, ExtensionIconSet::MATCH_EXACTLY));
 }
 
 TEST_F(ExtensionManifestTest, ValidIconSizes) {