Add an API for hosted apps to check their install and running states.

chrome/common/extensions/url_pattern.cc

Index: chrome/common/extensions/url_pattern.cc
diff --git a/chrome/common/extensions/url_pattern.cc b/chrome/common/extensions/url_pattern.cc
index c0b04b7cf6eceb963b0693720c35d305849e8300..c77e61c8082c88fc900b32a5a8e9049738af7074 100644
--- a/chrome/common/extensions/url_pattern.cc
+++ b/chrome/common/extensions/url_pattern.cc
@@ -378,10 +378,9 @@ bool URLPattern::MatchesHost(const GURL& test) const {
 }
 
 bool URLPattern::MatchesPath(const std::string& test) const {
-  if (!MatchPattern(test, path_escaped_))
-    return false;
-
-  return true;
+  return MatchPattern(test, path_escaped_) ||
+      MatchPattern(test + '/', path_escaped_) ||
+      MatchPattern(test, path_escaped_ + '/');

[jstritar, 2012/04/22 17:57:31]

I did this because some apps, like Google Finance, define their extents as
"http://www.google.com/finance/" but they are actually located at
"http://www.google.com/finance". How do you think we should address that?

[miket_OOO, 2012/04/23 22:11:16]

I'd prefer to force developers to get it exactly right than to support loose
matching forever. If someone believes their webserver isn't predictably going to
302 them over to the desired URL (finance to finance/ or vice-versa), they can
include two patterns (finance and finance/) in their extents list.

Also, I think this method is used in other contexts, too (content scripts), and
from its name it could be used in future contexts, so I think it's better to go
with the least surprising behavior (MatchesPath = exactly matches, not loose
matching).

Finally, I would smack anyone who did this, but you could see /foo and /foo/
doing totally different things on a webserver, so I'm not sure it's a safe
assumption that everyone meant them to be equivalent.

[jstritar, 2012/04/23 23:46:12]

Agreed... if we do any fuzzy matching it probably shouldn't be in the
URLPattern, but when we create the app's extent (if at all). 
Removed the change from the CL.

 }
 
 bool URLPattern::MatchesPort(int port) const {