Replace 'ap' with 'up' suffix in variable names. (NFC)

The `ap` suffix is a remnant of lldb's former use of auto pointers,
before they got deprecated. Although all their uses were replaced by
unique pointers, some variables still carried the suffix.

In r353795 I removed another auto_ptr remnant, namely redundant calls to
::get for unique_pointers. Jim justly noted that this is a good
opportunity to clean up the variable names as well.

I went over all the changes to ensure my find-and-replace didn't have
any undesired side-effects. I hope I didn't miss any, but if you end up
at this commit doing a git blame on a weirdly named variable, please
know that the change was unintentional.

llvm-svn: 353912
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp
index fb72d67..bc725c9 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp
@@ -489,13 +489,13 @@
   // Parse the expression
   //
 
-  m_materializer_ap.reset(new Materializer());
+  m_materializer_up.reset(new Materializer());
 
   ResetDeclMap(exe_ctx, m_result_delegate, keep_result_in_memory);
 
   OnExit on_exit([this]() { ResetDeclMap(); });
 
-  if (!DeclMap()->WillParse(exe_ctx, m_materializer_ap.get())) {
+  if (!DeclMap()->WillParse(exe_ctx, m_materializer_up.get())) {
     diagnostic_manager.PutString(
         eDiagnosticSeverityError,
         "current process state is unsuitable for expression parsing");
@@ -678,13 +678,13 @@
   // Parse the expression
   //
 
-  m_materializer_ap.reset(new Materializer());
+  m_materializer_up.reset(new Materializer());
 
   ResetDeclMap(exe_ctx, m_result_delegate, /*keep result in memory*/ true);
 
   OnExit on_exit([this]() { ResetDeclMap(); });
 
-  if (!DeclMap()->WillParse(exe_ctx, m_materializer_ap.get())) {
+  if (!DeclMap()->WillParse(exe_ctx, m_materializer_up.get())) {
     diagnostic_manager.PutString(
         eDiagnosticSeverityError,
         "current process state is unsuitable for expression parsing");