fix(composer): Temporary patch for broken focus

Long term, we need to refactor this so that it's either entirely controlled or uncontrolled. Potentially use focusin?

internal_packages/composer/lib/composer-editor.jsx

@@ -70,6 +70,7 @@ class ComposerEditor extends Component {
     draftClientId: PropTypes.string,
     initialSelectionSnapshot: PropTypes.object,
     onFocus: PropTypes.func.isRequired,
+    onBlur: PropTypes.func.isRequired,
     onFilePaste: PropTypes.func.isRequired,
     onBodyChanged: PropTypes.func.isRequired,
     parentActions: PropTypes.shape({
@@ -85,6 +86,7 @@ class ComposerEditor extends Component {
     };
     this._coreExtension = {
       onFocus: props.onFocus,
+      onBlur: props.onBlur,
     };
   }
 

internal_packages/composer/lib/composer-view.cjsx

@@ -269,8 +269,8 @@ class ComposerView extends React.Component
     @_onChangeFocusedField(enabledFields[newI])
 
   _onChangeFocusedField: (focusedField) =>
-    @setState {focusedField}
-    if focusedField in [Fields.To, Fields.Cc, Fields.Bcc]
+    @setState({focusedField})
+    if focusedField in Fields.ParticipantFields
       @_lastFocusedParticipantField = focusedField
 
   _onExpandParticipantFields: =>
@@ -296,7 +296,7 @@ class ComposerView extends React.Component
                ref={Fields.Subject}
                placeholder="Subject"
                value={@state.subject}
-               onFocus={ => @setState focusedField: Fields.Subject}
+               onFocus={ => @setState(focusedField: Fields.Subject) }
                onChange={@_onChangeSubject}/>
       </div>
 
@@ -316,7 +316,8 @@ class ComposerView extends React.Component
         scrollTo: @props.scrollTo
       }
       initialSelectionSnapshot: @_recoveredSelection
-      onFocus: @_onEditorFocus
+      onFocus: => @setState(focusedField: Fields.Body)
+      onBlur: => @setState(focusedField: null)
       onFilePaste: @_onFilePaste
       onBodyChanged: @_onBodyChanged
 
@@ -340,9 +341,6 @@ class ComposerView extends React.Component
   _onEditorBodyDidRender: =>
     @_applyFieldFocus()
 
-  _onEditorFocus: =>
-    @setState(focusedField: Fields.Body)
-
   # The contenteditable decides when to request a scroll based on the
   # position of the cursor and its relative distance to this composer
   # component. We provide it our boundingClientRect so it can calculate