Fabric: Virtual destructors for all abstract interface-like classes

Summary:
@public
Apparently, it's how it should be.

Reviewed By: rsnara

Differential Revision: D9631870

fbshipit-source-id: 46f58270104d699fbc9abe21062c12f791460536

ReactCommon/fabric/uimanager/SchedulerDelegate.h

@@ -18,10 +18,8 @@ namespace react {
  * Abstract class for Scheduler's delegate.
  */
 class SchedulerDelegate {
+
 public:
-
-  virtual ~SchedulerDelegate() = default;
-
   /*
    * Called right after Scheduler computed (and laid out) a new updated version
    * of the tree and calculated a set of mutations which are suffisient
@@ -33,6 +31,8 @@ public:
    * Called right after a new ShadowNode was created.
    */
   virtual void schedulerDidRequestPreliminaryViewAllocation(ComponentName componentName) = 0;
+
+  virtual ~SchedulerDelegate() noexcept = default;
 };
 
 } // namespace react

ReactCommon/fabric/uimanager/ShadowTreeDelegate.h

@@ -16,12 +16,14 @@ class ShadowTree;
  * Abstract class for ShadowTree's delegate.
  */
 class ShadowTreeDelegate {
-public:
 
+public:
   /*
    * Called right after Shadow Tree commit a new state of the the tree.
    */
   virtual void shadowTreeDidCommit(const ShadowTree &shadowTree, const ShadowViewMutationList &mutations) = 0;
+
+  virtual ~ShadowTreeDelegate() noexcept = default;
 };
 
 } // namespace react

ReactCommon/fabric/uimanager/UIManagerDelegate.h

@@ -17,8 +17,8 @@ namespace react {
  * Abstract class for UIManager's delegate.
  */
 class UIManagerDelegate {
-public:
 
+public:
   /*
    * Called right after the new/updated Shadow Node tree is constructed.
    * The tree is not layed out and not sealed at this time.
@@ -31,6 +31,8 @@ public:
    * instances.
    */
   virtual void uiManagerDidCreateShadowNode(const SharedShadowNode &shadowNode) = 0;
+
+  virtual ~UIManagerDelegate() noexcept = default;
 };
 
 } // namespace react