[Aura] Initial app list webui.

chrome/common/url_constants.h

Index: chrome/common/url_constants.h
diff --git a/chrome/common/url_constants.h b/chrome/common/url_constants.h
index 437c9937b50e35762217214cd9fefb167a45c176..0e896d5a76deb817219a9ae577bd83cd004b0a1d 100644
--- a/chrome/common/url_constants.h
+++ b/chrome/common/url_constants.h
@@ -100,6 +100,10 @@ extern const char kChromeUIHttpAuthURL[];
 extern const char kChromeUIRepostFormWarningURL[];
 #endif
 
+#if defined(USE_AURA)
+extern const char kChromeUIAppListURL[];
+#endif
+
 // chrome components of URLs. Should be kept in sync with the full URLs above.
 extern const char kChromeUIAboutHost[];
 extern const char kChromeUIAppCacheInternalsHost[];
@@ -224,6 +228,10 @@ extern const char kChromeUIHttpAuthHost[];
 extern const char kChromeUIRepostFormWarningHost[];
 #endif
 
+#if defined(USE_AURA)
+extern const char kChromeUIAppListHost[];
+#endif
+
 // Options sub-pages.
 extern const char kAdvancedOptionsSubPage[];
 extern const char kAutofillSubPage[];