eina: Add missing eina_internal.h

src/Makefile_Eina.am

@@ -391,6 +391,7 @@ EXTRA_DIST2 += \
 lib/eina/eina_strbuf_template_c.x \
 lib/eina/eina_binbuf_template_c.x \
 lib/eina/eina_inline_private.h \
+lib/eina/eina_internal.h \
 tests/eina/sample.gpx \
 tests/eina/eina_suite.x \
 lib/eina/eina_config.h.in \

src/lib/eina/eina_internal.h

@@ -0,0 +1,16 @@
+#ifndef EINA_INTERNAL_H
+#define EINA_INTERNAL_H
+
+/*
+ * eina_internal.h
+ *
+ * Lists public functions that are meant for internal use by EFL only and are
+ * not stable API.
+ */
+
+/**
+ * @brief Cancels all pending promise/futures.
+ */
+EAPI void __eina_promise_cancel_all(void);
+
+#endif