General comment cleaning / refactoring for Mac Installer

chrome/installer/mac/app/OmahaXMLParser.m

Index: chrome/installer/mac/app/OmahaXMLParser.m
diff --git a/chrome/installer/mac/app/OmahaXMLParser.m b/chrome/installer/mac/app/OmahaXMLParser.m
index fa901b2eb3a0f40b74dc4eb9903e6fc96be17c81..2493b8dc72f09bfa8444166d75bb82bda56b0935 100644
--- a/chrome/installer/mac/app/OmahaXMLParser.m
+++ b/chrome/installer/mac/app/OmahaXMLParser.m
@@ -32,9 +32,10 @@
   }
 
   if ([completeDownloadURLs count] < 1) {
-    // TODO: currently whatever error is passed in doesn't matter... we should
-    // make it so that the type of error informs what the installer will do
-    // about the error
+    // TODO: The below error exists only so the caller of this method would
+    // catch the error created here. A better way to handle this is to make the
+    // error's contents inform what the installer will try next when it attempts
+    // to recover from an issue.
     *error = [NSError errorWithDomain:@"ChromeErrorDomain" code:1 userInfo:nil];
     return nil;
   }
@@ -42,10 +43,9 @@
   return completeDownloadURLs;
 }
 
-// Method implementation for XMLParserDelegate.
 // Searches the XML data for the tag "URL" and the subsequent "codebase"
 // attribute that indicates a URL follows. Copies each URL into an array.
-// Note that the URLs in the XML file are incomplete. They need the filename
+// NOTE: The URLs in the XML file are incomplete. They need the filename
 // appended to end. The second if statement checks for the tag "package" which
 // contains the filename needed to complete the URLs.
 - (void)parser:(NSXMLParser*)parser