Fix application of composition to multiple cursors

FIX: Fix a bug that broke insertion of composed input at multiple cursors when
the IME keeps the selection at the start of the composed text.

Closes codemirror/dev#1637

Author: marijnh

src/domchange.ts

@@ -209,7 +209,7 @@ function applyDefaultInsert(view: EditorView, change: {from: number, to: number,
     let mainSel = newSel && newSel.main.to <= changes.newLength ? newSel.main : undefined
     // Try to apply a composition change to all cursors
     if (startState.selection.ranges.length > 1 && view.inputState.composing >= 0 &&
-        change.to <= sel.to && change.to >= sel.to - 10) {
+        change.to <= sel.to + 10 && change.to >= sel.to - 10) {
       let replaced = view.state.sliceDoc(change.from, change.to)
       let compositionRange: {from: number, to: number}, composition = newSel && findCompositionNode(view, newSel.main.head)
       if (composition) {