Don't use finally in the operation that initializes the editor

Trying to call endOperation on a half-constructed editor will never end
well, and the resulting errors will mask the actual error that happened.

Author: marijnh

lib/codemirror.js

@@ -96,21 +96,20 @@
     registerEventHandlers(this);
     ensureGlobalHandlers();
 
-    var cm = this;
-    runInOp(this, function() {
-      cm.curOp.forceUpdate = true;
-      attachDoc(cm, doc);
+    startOperation(this);
+    this.curOp.forceUpdate = true;
+    attachDoc(this, doc);
 
-      if ((options.autofocus && !mobile) || activeElt() == display.input)
-        setTimeout(bind(onFocus, cm), 20);
-      else
-        onBlur(cm);
+    if ((options.autofocus && !mobile) || activeElt() == display.input)
+      setTimeout(bind(onFocus, this), 20);
+    else
+      onBlur(this);
 
-      for (var opt in optionHandlers) if (optionHandlers.hasOwnProperty(opt))
-        optionHandlers[opt](cm, options[opt], Init);
-      maybeUpdateLineNumberWidth(cm);
-      for (var i = 0; i < initHooks.length; ++i) initHooks[i](cm);
-    });
+    for (var opt in optionHandlers) if (optionHandlers.hasOwnProperty(opt))
+      optionHandlers[opt](this, options[opt], Init);
+    maybeUpdateLineNumberWidth(this);
+    for (var i = 0; i < initHooks.length; ++i) initHooks[i](this);
+    endOperation(this);
   }
 
   // DISPLAY CONSTRUCTOR