DevTools: Roll CodeMirror to 5.25.1

third_party/WebKit/Source/devtools/front_end/cm/markselection.js

 // CodeMirror, copyright (c) by Marijn Haverbeke and others
 // Distributed under an MIT license: http://codemirror.net/LICENSE
 
 // Because sometimes you need to mark the selected *text*.
 //
 // Adds an option 'styleSelectedText' which, when enabled, gives
 // selected text the CSS class given as option value, or
 // "CodeMirror-selectedtext" when the value is not a string.
 
 (function(mod) {
@@ skipping 16 matching lines @@
       cm.on("change", onChange);
     } else if (!val && prev) {
       cm.off("cursorActivity", onCursorActivity);
       cm.off("change", onChange);
       clear(cm);
       cm.state.markedSelection = cm.state.markedSelectionStyle = null;
     }
   });
 
   function onCursorActivity(cm) {
-    cm.operation(function() { update(cm); });
+    if (cm.state.markedSelection)
+      cm.operation(function() { update(cm); });
   }
 
   function onChange(cm) {
-    if (cm.state.markedSelection.length)
+    if (cm.state.markedSelection && cm.state.markedSelection.length)
       cm.operation(function() { clear(cm); });
   }
 
   var CHUNK_SIZE = 8;
   var Pos = CodeMirror.Pos;
   var cmp = CodeMirror.cmpPos;
 
   function coverRange(cm, from, to, addAt) {
     if (cmp(from, to) == 0) return;
     var array = cm.state.markedSelection;
@@ skipping 57 matching lines @@
     if (cmp(to, coverEnd.to) > 0) {
       if (to.line - coverEnd.from.line < CHUNK_SIZE) {
         array.pop().clear();
         coverRange(cm, coverEnd.from, to);
       } else {
         coverRange(cm, coverEnd.to, to);
       }
     }
   }
 });