Clarify the 'frame variable' help message regarding the watchpoint functionality.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@150039 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Commands/CommandObjectFrame.cpp b/source/Commands/CommandObjectFrame.cpp
index cec5090..f1d51a1 100644
--- a/source/Commands/CommandObjectFrame.cpp
+++ b/source/Commands/CommandObjectFrame.cpp
@@ -331,7 +331,10 @@
                        "argument, local, file static and file global variables. "
                        "Children of aggregate variables can be specified such as "
                        "'var->child.x'. "
-                       "You can choose to watch a variable with the '-w' option. "
+                       "You can choose to watch a variable with the '-w' option; "
+                       "with the additional '-x' option to specify the region size, "
+                       "the variable's value will be used as the starting address of "
+                       "the region to watch for, instead. "
                        "Note that hardware resources for watching are often limited. "
                        "See alo 'watchpoint set' where you can use an expression to "
                        "specify the address to watch for.",