fix(core): update core to handle reset context

- range check vk
- split modifier test out to separate function

core/src/km_core_state_api.cpp

@@ -384,10 +384,7 @@ state_should_invalidate_context(km_core_state *state,
     if (vk == KM_CORE_VKEY_BKSP && state->context().empty()) {
         return true; // context is empty - so pass back
     } else if (is_key_down &&
-              // either a ctrl or alt modifier
-                ((modifier_state & (K_CTRLFLAG | K_ALTFLAG | LCTRLFLAG | RCTRLFLAG | LALTFLAG | RALTFLAG))
-              // or a frame key
-              || vkey_to_contextreset[vk])) {
+          (modifier_should_contextreset(modifier_state) || vkey_should_contextreset(vk))) {
       return true;
     }
   }

core/src/vkey_to_contextreset.hpp

@@ -1,10 +1,26 @@
 #pragma once
 
+#include <iterator>
+#include <keyman/keyman_core_api.h>
+#include "kmx_file.h"
+
 namespace km {
 namespace core {
 
 /** true for any vkeys which require a context reset (such as frame keys) */
 extern bool vkey_to_contextreset[256];
 
+/** @return true for any vkeys which require a context reset (such as frame keys) */
+inline bool vkey_should_contextreset(km_core_virtual_key vk) {
+  return ((vk < std::size(vkey_to_contextreset)) && vkey_to_contextreset[vk]);
+}
+
+/** @return true for modifier states that are involved with context reset */
+inline bool modifier_should_contextreset(uint16_t modifier_state) {
+    // ctrl or alt
+    return (modifier_state & (K_CTRLFLAG | K_ALTFLAG | LCTRLFLAG | RCTRLFLAG | LALTFLAG | RALTFLAG));
+}
+
+
 }
 }