Fix autocomplete behavior for Android chrome.

Based off facebookarchive#175, this commit
fixes some issues with autocomplete behavior on Android Chrome.

.gitignore

@@ -9,3 +9,4 @@
 /website/src/draft-js/lib/
 /website/src/draft-js/docs/
 npm-debug.log
+.idea/

src/component/handlers/composition/DraftEditorCompositionHandler.js

@@ -42,6 +42,7 @@ const RESOLVE_DELAY = 20;
 let resolved = false;
 let stillComposing = false;
 let textInputData = '';
+let formerTextInputData = '';
 
 var DraftEditorCompositionHandler = {
   onBeforeInput: function(editor: DraftEditor, e: SyntheticInputEvent): void {
@@ -52,7 +53,8 @@ var DraftEditorCompositionHandler = {
    * A `compositionstart` event has fired while we're still in composition
    * mode. Continue the current composition session to prevent a re-render.
    */
-  onCompositionStart: function(editor: DraftEditor): void {
+  onCompositionStart: function(editor: DraftEditor, e: SyntheticInputEvent): void {
+    formerTextInputData = e.data;
     stillComposing = true;
   },
 
@@ -136,6 +138,9 @@ var DraftEditorCompositionHandler = {
     const composedChars = textInputData;
     textInputData = '';
 
+    const formerComposedChars = formerTextInputData;
+    formerTextInputData = '';
+
     const editorState = EditorState.set(editor._latestEditorState, {
       inCompositionMode: false,
     });
@@ -159,12 +164,28 @@ var DraftEditorCompositionHandler = {
 
     editor.exitCurrentMode();
 
+    let contentState = editorState.getCurrentContent();
+    let selection = editorState.getSelection();
+    if (formerComposedChars && selection.isCollapsed()) {
+      let anchorOffset = selection.getAnchorOffset() - formerComposedChars.length;
+      if (anchorOffset < 0) {
+        anchorOffset = 0;
+      }
+      const toRemoveSel = selection.merge({anchorOffset});
+      contentState = DraftModifier.removeRange(
+        editorState.getCurrentContent(),
+        toRemoveSel,
+        'backward',
+      );
+      selection = contentState.getSelectionAfter();
+    }
+
     if (composedChars) {
       // If characters have been composed, re-rendering with the update
       // is sufficient to reset the editor.
-      const contentState = DraftModifier.replaceText(
-        editorState.getCurrentContent(),
-        editorState.getSelection(),
+      contentState = DraftModifier.replaceText(
+        contentState,
+        selection,
         composedChars,
         currentStyle,
         entityKey

src/component/handlers/edit/editOnInput.js

@@ -23,6 +23,7 @@ var nullthrows = require('nullthrows');
 import type DraftEditor from 'DraftEditor.react';
 
 var isGecko = UserAgent.isEngine('Gecko');
+var isAndroid = UserAgent.isPlatform('Android');
 
 var DOUBLE_NEWLINE = '\n\n';
 
@@ -47,7 +48,7 @@ function editOnInput(editor: DraftEditor): void {
   var domSelection = global.getSelection();
 
   var {anchorNode, isCollapsed} = domSelection;
-  if (anchorNode.nodeType !== Node.TEXT_NODE) {
+  if (anchorNode.nodeType !== Node.TEXT_NODE && anchorNode.nodeType !== Node.ELEMENT_NODE) {
     return;
   }
 
@@ -107,7 +108,7 @@ function editOnInput(editor: DraftEditor): void {
 
   var anchorOffset, focusOffset, startOffset, endOffset;
 
-  if (isGecko) {
+  if (isAndroid || isGecko) {
     // Firefox selection does not change while the context menu is open, so
     // we preserve the anchor and focus values of the DOM selection.
     anchorOffset = domSelection.anchorOffset;