NaClApplication: fix improper assertion.

Apparently input events can be processed during buffer swapping. Now
asserting that callback from buffer swap is not called during input
event processing (which shouldn't, as both functions should be called in
the same thread).

src/Platform/NaClApplication.cpp

@@ -79,8 +79,7 @@ void NaClApplication::DidChangeView(const pp::View& view) {
 }
 
 bool NaClApplication::HandleInputEvent(const pp::InputEvent& event) {
-    /* Assume everything is properly sequential here */
-    CORRADE_INTERNAL_ASSERT(!(flags & Flag::SwapInProgress));
+    Flags tmpFlags = flags;
 
     switch(event.GetType()) {
         case PP_INPUTEVENT_TYPE_KEYDOWN:
@@ -112,12 +111,15 @@ bool NaClApplication::HandleInputEvent(const pp::InputEvent& event) {
         default: return false;
     }
 
-    /* Not need to redraw => assume the event was ignored */
-    if(!(flags & Flag::Redraw)) return false;
+    /* Assume everything is properly sequential here */
+    CORRADE_INTERNAL_ASSERT((tmpFlags & Flag::SwapInProgress) == (flags & Flag::SwapInProgress));
+
+    /* Redraw, if it won't be handled after swap automatically */
+    if((flags & Flag::Redraw) && !(flags & Flag::SwapInProgress)) {
+        flags &= ~Flag::Redraw;
+        drawEvent();
+    }
 
-    /* Redraw */
-    flags &= ~Flag::Redraw;
-    drawEvent();
     return true;
 }