Add a chrome://nacl page to show if NaCl is enabled and if PNaCl is installed.

chrome/common/url_constants.cc

Index: chrome/common/url_constants.cc
diff --git a/chrome/common/url_constants.cc b/chrome/common/url_constants.cc
index df254b3f303d2879a015d3171c27f83af19b4140..a651cf0b5a97779288a6df7f8f61210a8241f523 100644
--- a/chrome/common/url_constants.cc
+++ b/chrome/common/url_constants.cc
@@ -57,6 +57,7 @@ const char kChromeUIKeyboardURL[] = "chrome://keyboard/";
 const char kChromeUIMemoryRedirectURL[] = "chrome://memory-redirect/";
 const char kChromeUIMemoryURL[] = "chrome://memory/";
 const char kChromeUIMetroFlowURL[] = "chrome://make-metro/";
+const char kChromeUINaClURL[] = "chrome://nacl/";
 const char kChromeUINetInternalsURL[] = "chrome://net-internals/";
 const char kChromeUINewProfile[] = "chrome://newprofile/";
 const char kChromeUINewTabURL[] = "chrome://newtab/";
@@ -173,6 +174,7 @@ const char kChromeUIMediaInternalsHost[] = "media-internals";
 const char kChromeUIMemoryHost[] = "memory";
 const char kChromeUIMemoryRedirectHost[] = "memory-redirect";
 const char kChromeUIMetroFlowHost[] = "make-metro";
+const char kChromeUINaClHost[] = "nacl";
 const char kChromeUINetInternalsHost[] = "net-internals";
 const char kChromeUINewTabHost[] = "newtab";
 const char kChromeUIOmniboxHost[] = "omnibox";