NestedMacroInstantiations -> NestedMacroExpansions

This is switches all the interfaces points (and most of the commenst
/ local variables I saw on my way through) regarding the
NestedMacroInstantiations bit.

The libclang enums corresponding to this state were renamed, but
a legacy enum was added with the old name, and the same value to keep
existing clients working. I've added a documentation blurb for it, but
let me know if there is a canonical way to document legacy elemenst of
the libclang interface.

No functionality changed here, even in tests.

llvm-svn: 135141
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index ad47645..5b0a52c 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -102,7 +102,7 @@
     ConcurrencyCheckValue(CheckUnlocked), 
     PreambleRebuildCounter(0), SavedMainFileBuffer(0), PreambleBuffer(0),
     ShouldCacheCodeCompletionResults(false),
-    NestedMacroInstantiations(true),
+    NestedMacroExpansions(true),
     CompletionCacheTopLevelHashValue(0),
     PreambleTopLevelHashValue(0),
     CurrentTopLevelHashValue(0),
@@ -934,8 +934,8 @@
   // If the main file has been overridden due to the use of a preamble,
   // make that override happen and introduce the preamble.
   PreprocessorOptions &PreprocessorOpts = Clang->getPreprocessorOpts();
-  PreprocessorOpts.DetailedRecordIncludesNestedMacroInstantiations
-    = NestedMacroInstantiations;
+  PreprocessorOpts.DetailedRecordIncludesNestedMacroExpansions
+    = NestedMacroExpansions;
   std::string PriorImplicitPCHInclude;
   if (OverrideMainBuffer) {
     PreprocessorOpts.addRemappedFile(OriginalSourceFile, OverrideMainBuffer);
@@ -1725,7 +1725,7 @@
                                              bool PrecompilePreamble,
                                              bool CompleteTranslationUnit,
                                              bool CacheCodeCompletionResults,
-                                             bool NestedMacroInstantiations) {  
+                                             bool NestedMacroExpansions) {  
   // Create the AST unit.
   llvm::OwningPtr<ASTUnit> AST;
   AST.reset(new ASTUnit(false));
@@ -1736,7 +1736,7 @@
   AST->CompleteTranslationUnit = CompleteTranslationUnit;
   AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
   AST->Invocation = CI;
-  AST->NestedMacroInstantiations = NestedMacroInstantiations;
+  AST->NestedMacroExpansions = NestedMacroExpansions;
   
   // Recover resources if we crash before exiting this method.
   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>
@@ -1762,7 +1762,7 @@
                                       bool CacheCodeCompletionResults,
                                       bool CXXPrecompilePreamble,
                                       bool CXXChainedPCH,
-                                      bool NestedMacroInstantiations) {
+                                      bool NestedMacroExpansions) {
   if (!Diags.getPtr()) {
     // No diagnostics engine was provided, so create our own diagnostics object
     // with the default options.
@@ -1829,7 +1829,7 @@
   AST->NumStoredDiagnosticsInPreamble = StoredDiagnostics.size();
   AST->StoredDiagnostics.swap(StoredDiagnostics);
   AST->Invocation = CI;
-  AST->NestedMacroInstantiations = NestedMacroInstantiations;
+  AST->NestedMacroExpansions = NestedMacroExpansions;
   
   // Recover resources if we crash before exiting this method.
   llvm::CrashRecoveryContextCleanupRegistrar<ASTUnit>