Escaping file names correctly. Also fixed a crush in chromeos debug build while saving a web page.

net/base/escape.h

Index: net/base/escape.h
diff --git a/net/base/escape.h b/net/base/escape.h
index 65903296f5dc2148af2e174f56cc18e633a3d0ba..c0a17e7d52b6b4b99cd2fae557daaddad9e6a702 100644
--- a/net/base/escape.h
+++ b/net/base/escape.h
@@ -21,8 +21,10 @@ NET_API std::string EscapePath(const std::string& path);
 
 // Escape application/x-www-form-urlencoded content.  This includes:
 // non-printable, non-7bit, and (including space)  ?>=<;+'&%$#"![\]^`{|}
-// Space is escaped as + and other special characters as %XX (hex).
-NET_API std::string EscapeUrlEncodedData(const std::string& path);
+// Space is escaped as + (if use_plus is true) and other special characters
+// as %XX (hex).
+NET_API std::string EscapeUrlEncodedData(const std::string& path,
+                                         bool use_plus = true);
 
 // Escape all non-ASCII input.
 NET_API std::string EscapeNonASCII(const std::string& input);