Clean up setting of preferences for reftest. (Bug 608030) r=roc a=blocking2.0:betaN+

layout/tools/reftest/reftest-cmdline.js

@@ -92,11 +92,24 @@ RefTestCmdLineHandler.prototype =
     ios.manageOfflineStatus = false;
     ios.offline = false;
 
-    /* Force sRGB as an output profile for color management before we load a
+    /**
-       window. */
+     * Manipulate preferences by adding to the *default* branch.  Adding
+     * to the default branch means the changes we make won't get written
+     * back to user preferences.
+     *
+     * We want to do this here rather than in reftest.js because it's
+     * important to force sRGB as an output profile for color management
+     * before we load a window.
+     */
     var prefs = Components.classes["@mozilla.org/preferences-service;1"].
-                getService(Components.interfaces.nsIPrefBranch2);
+                getService(Components.interfaces.nsIPrefService);
-    prefs.setBoolPref("gfx.color_management.force_srgb", true);
+    var branch = prefs.getDefaultBranch("");
+    branch.setBoolPref("gfx.color_management.force_srgb", true);
+    branch.setBoolPref("browser.dom.window.dump.enabled", true);
+    branch.setIntPref("ui.caretBlinkTime", -1);
+    // no slow script dialogs
+    branch.setIntPref("dom.max_script_run_time", 0);
+    branch.setIntPref("dom.max_chrome_script_run_time", 0);
 
     var wwatch = Components.classes["@mozilla.org/embedcomp/window-watcher;1"]
                            .getService(nsIWindowWatcher);

layout/tools/reftest/reftest.js

@@ -359,11 +359,6 @@ function StartTests()
 
 function OnRefTestUnload()
 {
-    /* Clear the sRGB forcing pref to leave the profile as we found it. */
-    var prefs = Components.classes["@mozilla.org/preferences-service;1"].
-                getService(Components.interfaces.nsIPrefBranch2);
-    prefs.clearUserPref("gfx.color_management.force_srgb");
-
     gBrowser.removeEventListener("load", OnDocumentLoad, true);
     MozillaFileLogger.close();
 }

layout/tools/reftest/runreftest.py

@@ -71,12 +71,11 @@ class RefTest(object):
     self.automation.setupPermissionsDatabase(profileDir,
       {'allowXULXBL': [('localhost', True), ('<file>', True)]})
 
-    # Set preferences.
+    # Set preferences for communication between our command line arguments
+    # and the reftest harness.  Preferences that are required for reftest
+    # to work should instead be set in reftest-cmdline.js .
     prefsFile = open(os.path.join(profileDir, "user.js"), "w")
-    prefsFile.write("""user_pref("browser.dom.window.dump.enabled", true);
-    """)
     prefsFile.write('user_pref("reftest.timeout", %d);\n' % (options.timeout * 1000))
-    prefsFile.write('user_pref("ui.caretBlinkTime", -1);\n')
 
     if options.totalChunks != None:
       prefsFile.write('user_pref("reftest.totalChunks", %d);\n' % options.totalChunks)
@@ -92,9 +91,6 @@ class RefTest(object):
         sys.exit(1)
       part = 'user_pref("%s", %s);\n' % (thispref[0], thispref[1])
       prefsFile.write(part)
-    # no slow script dialogs
-    prefsFile.write('user_pref("dom.max_script_run_time", 0);')
-    prefsFile.write('user_pref("dom.max_chrome_script_run_time", 0);')
     prefsFile.close()
 
     # install the reftest extension bits into the profile