ProjectExplorer: Use Core::Id as RunMode "enum values"

This provides a way for third-party plugins to implement run
modes without the need to add a value to the central enum or
using manual workarounds like RunMode(*(int*)&someUniqueObject).

Instead of centrally defined enum values this uses Core::Id that could
be defined anywhere.

Change-Id: Ic350e3d8dbb8042c61b2d4ffec993ca151f53099
Reviewed-by: Daniel Teske <daniel.teske@theqtcompany.com>
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/plugins/valgrind/memchecktool.h

@@ -50,6 +50,10 @@ class Error;
 }
 
 namespace Valgrind {
+
+const char MEMCHECK_RUN_MODE[] = "MemcheckTool.MemcheckRunMode";
+const char MEMCHECK_WITH_GDB_RUN_MODE[] = "MemcheckTool.MemcheckWithGdbRunMode";
+
 namespace Internal {
 
 class FrameFinder;
@@ -57,6 +61,7 @@ class MemcheckErrorView;
 class MemcheckRunControl;
 class ValgrindBaseSettings;
 
+
 class MemcheckErrorFilterProxyModel : public QSortFilterProxyModel
 {
     Q_OBJECT