Backout of 133382 patch to see if it's causing the Tp regression.

xpfe/browser/resources/content/nsBrowserStatusHandler.js

@@ -170,11 +170,6 @@ nsBrowserStatusHandler.prototype =
       this.statusTextField.label = text;
   },
 
-  mimeTypeIsTextBased : function(contentType)
-  {
-    return /^text\/|\+xml$/.test(contentType);
-  },
-
   onLinkIconAvailable : function(aHref) {
     if (gProxyFavIcon && pref.getBoolPref("browser.chrome.site_icons"))
     {
@@ -228,6 +223,7 @@ nsBrowserStatusHandler.prototype =
         this.stopButton.disabled = false;
         this.stopMenu.removeAttribute('disabled');
         this.stopContext.removeAttribute('disabled');
+        this.isImage.removeAttribute('disabled');
 
         // Initialize the progress stuff...
         this.useRealProgressFlag = false;
@@ -262,9 +258,7 @@ nsBrowserStatusHandler.prototype =
           this.setDefaultStatus(msg);
           try {
             ctype = aRequest.QueryInterface(nsIChannel).contentType;
-            if (this.mimeTypeIsTextBased(ctype)) 
-              this.isImage.removeAttribute('disabled');
-            else
+            if (ctype.match(/^image\//))
               this.isImage.setAttribute('disabled', 'true');
           }
           catch (e) {}
@@ -309,12 +303,6 @@ nsBrowserStatusHandler.prototype =
         location = "";
     }
 
-    // Disable menu entries for images, enable otherwise
-    if (this.mimeTypeIsTextBased(content.document.contentType))
-      this.isImage.removeAttribute('disabled');
-    else
-      this.isImage.setAttribute('disabled', 'true');
-
     // We should probably not do this if the value has changed since the user
     // searched
     // Update urlbar only if a new page was loaded on the primary content area