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/Symbol/SymbolFile.cpp b/lldb/source/Symbol/SymbolFile.cpp
index 85242ae..e55b997 100644
--- a/lldb/source/Symbol/SymbolFile.cpp
+++ b/lldb/source/Symbol/SymbolFile.cpp
@@ -102,7 +102,7 @@
 }
 
 uint32_t
-SymbolFile::FindGlobalVariables(const ConstString &name,
+SymbolFile::FindGlobalVariables(ConstString name,
                                 const CompilerDeclContext *parent_decl_ctx,
                                 uint32_t max_matches, VariableList &variables) {
   return 0;
@@ -114,7 +114,7 @@
   return 0;
 }
 
-uint32_t SymbolFile::FindFunctions(const ConstString &name,
+uint32_t SymbolFile::FindFunctions(ConstString name,
                                    const CompilerDeclContext *parent_decl_ctx,
                                    lldb::FunctionNameType name_type_mask,
                                    bool include_inlines, bool append,
@@ -139,7 +139,7 @@
 }
 
 uint32_t SymbolFile::FindTypes(
-    const ConstString &name, const CompilerDeclContext *parent_decl_ctx,
+    ConstString name, const CompilerDeclContext *parent_decl_ctx,
     bool append, uint32_t max_matches,
     llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
     TypeMap &types) {