Android: add hint SDL_HINT_ANDROID_BLOCK_ON_PAUSE

to set whether the event loop will block itself when the app is paused.

include/SDL_hints.h

@@ -887,6 +887,17 @@ extern "C" {
  */
 #define SDL_HINT_ANDROID_TRAP_BACK_BUTTON "SDL_ANDROID_TRAP_BACK_BUTTON"
 
+/**
+ * \brief A variable to control whether the event loop will block itself when the app is paused.
+ *
+ * The variable can be set to the following values:
+ *   "0"       - Non blocking.
+ *   "1"       - Blocking. (default)
+ *
+ * The value should be set before SDL is initialized.
+ */
+#define SDL_HINT_ANDROID_BLOCK_ON_PAUSE "SDL_ANDROID_BLOCK_ON_PAUSE"
+
  /**
  * \brief A variable to control whether the return key on the soft keyboard
  *        should hide the soft keyboard on Android and iOS.