Make character text changes work in Docs

chrome/browser/resources/chromeos/chromevox/cvox2/background/editing.js

Index: chrome/browser/resources/chromeos/chromevox/cvox2/background/editing.js
diff --git a/chrome/browser/resources/chromeos/chromevox/cvox2/background/editing.js b/chrome/browser/resources/chromeos/chromevox/cvox2/background/editing.js
index f69e70fdc42124976b7b6fe3cfea6baca0ec4138..f0d773e38aa94411b3a2abd1871cfbe994d458a1 100644
--- a/chrome/browser/resources/chromeos/chromevox/cvox2/background/editing.js
+++ b/chrome/browser/resources/chromeos/chromevox/cvox2/background/editing.js
@@ -662,6 +662,8 @@ editing.EditableLine = function(
   this.lineEndContainer_;
   /** @private {number} */
   this.localLineEndContainerOffset_ = 0;
+  /** @type {Cursor} */
+  this.lineStartContainerCursor_;
 
   this.computeLineData_(opt_baseLineOnStart);
 };
@@ -767,6 +769,11 @@ editing.EditableLine.prototype = {
     }
     this.localLineStartContainerOffset_ = textCountBeforeLineStart;
 
+    if (this.lineStartContainer_) {
+      this.lineStartContainerCursor_ = new Cursor(
+          this.lineStartContainer_, this.localLineStartContainerOffset_);
+    }
+
     finder = this.lineEnd_;
     while (finder.nextSibling) {
       finder = finder.nextSibling;
@@ -909,7 +916,11 @@ editing.EditableLine.prototype = {
                 this.localLineStartContainerOffset_) ||
         (otherLine.lineEndContainer_ == this.lineEndContainer_ &&
          otherLine.localLineEndContainerOffset_ ==
-             this.localLineEndContainerOffset_);
+             this.localLineEndContainerOffset_) ||
+        (otherLine.lineStartContainerCursor_.recoveryNode ==
+             this.lineStartContainerCursor_.recoveryNode &&
+         otherLine.lineStartContainerCursor_.index ==
+             this.lineStartContainerCursor_.index);
   },
 
   /**