Adapt loplugins to clang-cl's (implicit) -fdelayed-template-parsing

...which is there for MSVC compatibility, but can cause getBody() to return null
even when doesThisDeclarationHaveABody() is true.

And in staticmethods.cxx we need to check doesThisDeclarationHaveABody() instead
of hasBody():  For some class template member functions that are only defined
outside their class definition, as is the case for
OSequenceIterator::hasMoreElements in include/comphelper/sequence.hxx, hasBody()
may be true for the original member function declaration inside the class (as
there is some later definition that does have a body), but
isLateTemplateParsed() is not (it is only true for the later definition).  So
just skip any such declarations that are not definitions (which is sane anyway,
as otherwise such functions could pointlessly be inspected multiple times).

Change-Id: I724f652a8f060a931f8b5fc3e4feb5f307a922bf
Reviewed-on: https://gerrit.libreoffice.org/42914
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>

compilerplugins/clang/plugin.cxx

@@ -206,7 +206,8 @@ bool ParentBuilder::VisitFunctionDecl( const FunctionDecl* function )
 {
 //    if( ignoreLocation( declaration ))
 //        return true; ???
-    if( function->doesThisDeclarationHaveABody())
+    if( function->doesThisDeclarationHaveABody()
+        && !function->isLateTemplateParsed())
     {
         const Stmt* body = function->getBody();
         (*parents)[ body ] = NULL; // no parent