Move "default for protocol" probing logic out of shell_integration_win.cc into shell_util.cc.

chrome/installer/util/shell_util.h

Index: chrome/installer/util/shell_util.h
diff --git a/chrome/installer/util/shell_util.h b/chrome/installer/util/shell_util.h
index a67a7243fb62c2564f76b264a5f2edc65a6a1431..745c0fcb2805d8a3eee19e89b3c2bd1b14ca39be 100644
--- a/chrome/installer/util/shell_util.h
+++ b/chrome/installer/util/shell_util.h
@@ -32,6 +32,13 @@ class ShellUtil {
     SYSTEM_LEVEL = 0x2   // Make any shell changes only at the system level
   };
 
+  // Chrome's default handler state for a given protocol.
+  enum DefaultState {
+    UNKNOWN_DEFAULT,
+    NOT_DEFAULT,
+    IS_DEFAULT,
+  };
+
   // Typical shortcut directories. Resolved in GetShortcutPath().
   enum ChromeShortcutLocation {
     SHORTCUT_DESKTOP,
@@ -379,6 +386,12 @@ class ShellUtil {
   // Windows prior to Windows 8.
   static bool CanMakeChromeDefaultUnattended();
 
+  // Returns true if Chrome is the default handler for HTTP and HTTPS.
+  static DefaultState IsChromeDefault();
+
+  // Returns true if Chrome is the default handler for |protocol|.
+  static DefaultState IsChromeDefaultProtocolClient(const string16& protocol);
+
   // Make Chrome the default browser. This function works by going through
   // the url protocols and file associations that are related to general
   // browsing, e.g. http, https, .html etc., and requesting to become the