Adding ThreadChecker validation to d'tors for host classes

remoting/host/mouse_shape_pump.cc

Index: remoting/host/mouse_shape_pump.cc
diff --git a/remoting/host/mouse_shape_pump.cc b/remoting/host/mouse_shape_pump.cc
index f86a30a853a26872a4709e2f9ad8451f8e6252a4..16a09a997c5d2ca15fed934e8e8a89f9fac7c4b3 100644
--- a/remoting/host/mouse_shape_pump.cc
+++ b/remoting/host/mouse_shape_pump.cc
@@ -32,7 +32,9 @@ MouseShapePump::MouseShapePump(
       base::Bind(&MouseShapePump::Capture, base::Unretained(this)));
 }
 
-MouseShapePump::~MouseShapePump() {}
+MouseShapePump::~MouseShapePump() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+}
 
 void MouseShapePump::Capture() {
   DCHECK(thread_checker_.CalledOnValidThread());