Add concrete type overloads to PDBSymbol::findChildren().

Frequently you only want to iterate over children of a specific
type (e.g. functions).  Previously you would get back a generic
interface that allowed iteration over the base symbol type,
which you would have to dyn_cast<> each one of.  With this patch,
we allow the user to specify the concrete type as a template
parameter, and it will return an iterator which returns instances
of the concrete type directly.

llvm-svn: 228960
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp
index f605af2..bffad8a 100644
--- a/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolData.cpp
@@ -25,9 +25,11 @@
   if (Level == PDB_DumpLevel::Compact) {
     PDB_LocType Loc = getLocationType();
     OS << Loc << " data [";
+    int Length;
     switch (Loc) {
     case PDB_LocType::Static:
       OS << format_hex(getRelativeVirtualAddress(), 10);
+      Length = getLength();
       break;
     case PDB_LocType::TLS:
       OS << getAddressSection() << ":" << format_hex(getAddressOffset(), 10);