Fixing 38767. Allows C: to be a valid path to InitWithPath();

xpcom/io/nsLocalFileWin.cpp

@@ -591,8 +591,17 @@ nsLocalFile::InitWithPath(const char *filePath)
     
     // just do a sanity check.  if it has any forward slashes, it is not a Native path
     // on windows.  Also, it must have a colon at after the first char.
+    if (filePath[0] == 0)
+        return NS_ERROR_FAILURE;
+    
+    if ( (filePath[2] == 0) && (filePath[1] == ':') )
+    {
+        nativeFilePath = (char*) nsAllocator::Clone( filePath, 4 );
+        // C : //
+        nativeFilePath[2] = '\\';
+    }
 
-    if ( ( (filePath[0] != 0) && (filePath[1] == ':') && (strchr(filePath, '/') == 0) ) ||  // normal windows path
+    if ( ( (filePath[1] == ':')  && (strchr(filePath, '/') == 0) ) ||  // normal windows path
          ( (filePath[0] == '\\') && (filePath[1] == '\\') ) )  // netwerk path
     {
         // This is a native path