<rdar://problem/10103468>

I started work on being able to add symbol files after a debug session
had started with a new "target symfile add" command and quickly ran into
problems with stale Address objects in breakpoint locations that had 
lldb_private::Section pointers into modules that had been removed or 
replaced. This also let to grabbing stale modules from those sections. 
So I needed to thread harded the Address, Section and related objects.

To do this I modified the ModuleChild class to now require a ModuleSP
on initialization so that a weak reference can created. I also changed
all places that were handing out "Section *" to have them hand out SectionSP.
All ObjectFile, SymbolFile and SymbolVendors were inheriting from ModuleChild
so all of the find plug-in, static creation function and constructors now
require ModuleSP references instead of Module *. 

Address objects now have weak references to their sections which can
safely go stale when a module gets destructed. 

This checkin doesn't complete the "target symfile add" command, but it
does get us a lot clioser to being able to do such things without a high
risk of crashing or memory corruption.




git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@151336 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Expression/ClangUserExpression.cpp b/source/Expression/ClangUserExpression.cpp
index a574e47..7a2541d 100644
--- a/source/Expression/ClangUserExpression.cpp
+++ b/source/Expression/ClangUserExpression.cpp
@@ -575,7 +575,7 @@
         const bool stop_others = true;
         const bool try_all_threads = true;
         
-        Address wrapper_address (NULL, m_jit_start_addr);
+        Address wrapper_address (m_jit_start_addr);
         lldb::ThreadPlanSP call_plan_sp(new ThreadPlanCallUserExpression (exe_ctx.GetThreadRef(), 
                                                                           wrapper_address, 
                                                                           struct_address,