minor cleanup with the stack-related fields in ThreadState:
- removed "stack_base" which wasn't used in any meaningful way
- added "client_" prefix to make it clear they concern the client's stack
- renamed "stack_size" as "client_stack_szB" to make the units clear



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@3516 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/stacktrace.c b/coregrind/stacktrace.c
index f8c7c4e..5821d58 100644
--- a/coregrind/stacktrace.c
+++ b/coregrind/stacktrace.c
@@ -116,7 +116,7 @@
    Addr ip                 = INSTR_PTR(tst->arch);
    Addr fp                 = FRAME_PTR(tst->arch);
    Addr sp                 = STACK_PTR(tst->arch);
-   Addr stack_highest_word = tst->stack_highest_word;
+   Addr stack_highest_word = tst->client_stack_highest_word;
 
 #ifdef __x86__
    /* Nasty little hack to deal with sysinfo syscalls - if libc is