[gnome-shell] Do not fail if json Python module is not available

[Frederic Peters <fpeters src gnome org>]

commit f1e31041286c27500cee5720b02a4193e3790009
Author: Frédéric Péters <fpeters 0d be>
Date:   Tue May 25 16:31:15 2010 +0200

    Do not fail if json Python module is not available
    
    Fallback to old simplejson module if present, and options that require
    the json module (create extension and performance) if absent.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=619580

 src/gnome-shell.in |   18 +++++++++++++++---
 1 files changed, 15 insertions(+), 3 deletions(-)
---
diff --git a/src/gnome-shell.in b/src/gnome-shell.in
index c1a439d..772a8cf 100644
--- a/src/gnome-shell.in
+++ b/src/gnome-shell.in
@@ -3,7 +3,13 @@
 
 import atexit
 import datetime
-import json
+try:
+    import json
+except ImportError:
+    try:
+        import simplejson as json
+    except ImportError:
+        json = None
 import optparse
 import os
 import random
@@ -548,9 +554,15 @@ if args:
     parser.print_usage()
     sys.exit(1)
 
-if options.create_extension:
-    import json
+if options.create_extension and json is None:
+    print 'The Python simplejson module is required to create a new GNOME Shell extension'
+    sys.exit(1)
+
+if options.perf and json is None:
+    print 'The Python simplejson module is required for performance tests'
+    sys.exit(1)
 
+if options.create_extension:
     print
     print '''Name should be a very short (ideally descriptive) string.
 Examples are: "Click To Focus",  "Adblock", "Shell Window Shrinker".