Pass ConstString by value (NFC)

My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.

ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.

(This fixes rdar://problem/48640859 for the Apple folks)

Differential Revision: https://reviews.llvm.org/D59030

llvm-svn: 355553
diff --git a/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp b/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
index 84b9e7f..30c8f9f 100644
--- a/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
+++ b/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
@@ -1046,7 +1046,7 @@
 }
 
 uint32_t SymbolFilePDB::FindGlobalVariables(
-    const lldb_private::ConstString &name,
+    lldb_private::ConstString name,
     const lldb_private::CompilerDeclContext *parent_decl_ctx,
     uint32_t max_matches, lldb_private::VariableList &variables) {
   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
@@ -1246,7 +1246,7 @@
 }
 
 uint32_t SymbolFilePDB::FindFunctions(
-    const lldb_private::ConstString &name,
+    lldb_private::ConstString name,
     const lldb_private::CompilerDeclContext *parent_decl_ctx,
     FunctionNameType name_type_mask, bool include_inlines, bool append,
     lldb_private::SymbolContextList &sc_list) {
@@ -1386,7 +1386,7 @@
 }
 
 uint32_t SymbolFilePDB::FindTypes(
-    const lldb_private::ConstString &name,
+    lldb_private::ConstString name,
     const lldb_private::CompilerDeclContext *parent_decl_ctx, bool append,
     uint32_t max_matches,
     llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
@@ -1628,7 +1628,7 @@
 
 
 lldb_private::CompilerDeclContext SymbolFilePDB::FindNamespace(
-    const lldb_private::ConstString &name,
+    lldb_private::ConstString name,
     const lldb_private::CompilerDeclContext *parent_decl_ctx) {
   auto type_system = GetTypeSystemForLanguage(lldb::eLanguageTypeC_plus_plus);
   auto clang_type_system = llvm::dyn_cast_or_null<ClangASTContext>(type_system);