DevTools: hide autocomplete when the autocompletion prefix is empty

Source/devtools/front_end/CodeMirrorTextEditor.js

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1696 matching lines @@
             this._anchorBox = this._anchorBoxForPosition(cursor.line, cursor.ch);
             this._suggestBox.setPosition(this._anchorBox);
         }
     },
 
     _onCursorActivity: function()
     {
         if (!this._suggestBox)
             return;
         var cursor = this._codeMirror.getCursor();
-        if (cursor.line !== this._prefixRange.startLine || cursor.ch > this._prefixRange.endColumn || cursor.ch < this._prefixRange.startColumn)
+        if (cursor.line !== this._prefixRange.startLine || cursor.ch > this._prefixRange.endColumn || cursor.ch <= this._prefixRange.startColumn)
             this.finishAutocomplete();
     },
 
     /**
      * @param {number} line
      * @param {number} column
      * @return {?AnchorBox}
      */
     _anchorBoxForPosition: function(line, column)
     {
@@ skipping 43 matching lines @@
     var backgroundColorRule = backgroundColor ? ".CodeMirror .CodeMirror-selected { background-color: " + backgroundColor + ";}" : "";
     var foregroundColor = InspectorFrontendHost.getSelectionForegroundColor();
     var foregroundColorRule = foregroundColor ? ".CodeMirror .CodeMirror-selectedtext:not(.CodeMirror-persist-highlight) { color: " + foregroundColor + "!important;}" : "";
     if (!foregroundColorRule && !backgroundColorRule)
         return;
 
     var style = document.createElement("style");
     style.textContent = backgroundColorRule + foregroundColorRule;
     document.head.appendChild(style);
 })();