[debugger] implement inspector-facing API for code coverage.

src/debug/interface-types.h

Index: src/debug/interface-types.h
diff --git a/src/debug/interface-types.h b/src/debug/interface-types.h
index ba6111d6fc20a2964a1a2aae2780dbc94c788c8b..b86986dee4c30719406d393253706c96a5129985 100644
--- a/src/debug/interface-types.h
+++ b/src/debug/interface-types.h
@@ -9,6 +9,8 @@
 #include <string>
 #include <vector>
 
+#include "src/globals.h"
+
 namespace v8 {
 namespace debug {
 
@@ -16,7 +18,7 @@ namespace debug {
  * Defines location inside script.
  * Lines and columns are 0-based.
  */
-class Location {
+class V8_EXPORT_PRIVATE Location {
  public:
   Location(int line_number, int column_number);
   /**