Recommit r368812 "[llvm/Object] - Convert SectionRef::getName() to return Expected<>"

Changes: no changes. A fix for the clang code will be landed right on top.

Original commit message:

SectionRef::getName() returns std::error_code now.
Returning Expected<> instead has multiple benefits.

For example, it forces user to check the error returned.
Also Expected<> may keep a valuable string error message,
what is more useful than having a error code.
(Object\invalid.test was updated to show the new messages printed.)

This patch makes a change for all users to switch to Expected<> version.

Note: in a few places the error returned was ignored before my changes.
In such places I left them ignored. My intention was to convert the interface
used, and not to improve and/or the existent users in this patch.
(Though I think this is good idea for a follow-ups to revisit such places
and either remove consumeError calls or comment each of them to clarify why
it is OK to have them).

Differential revision: https://reviews.llvm.org/D66089

llvm-svn: 368826
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
index f73d1c6..4b32862 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -535,9 +535,10 @@
       bool IsCode = Section.isText();
       bool IsReadOnly = isReadOnlyData(Section);
 
-      StringRef Name;
-      if (auto EC = Section.getName(Name))
-        return errorCodeToError(EC);
+      Expected<StringRef> NameOrErr = Section.getName();
+      if (!NameOrErr)
+        return NameOrErr.takeError();
+      StringRef Name = *NameOrErr;
 
       uint64_t StubBufSize = computeSectionStubBufSize(Obj, Section);
 
@@ -777,9 +778,10 @@
   // anyway, so we should guarantee that the alignment is always at least 1.
   Alignment = std::max(1u, Alignment);
 
-  StringRef Name;
-  if (auto EC = Section.getName(Name))
-    return errorCodeToError(EC);
+  Expected<StringRef> NameOrErr = Section.getName();
+  if (!NameOrErr)
+    return NameOrErr.takeError();
+  StringRef Name = *NameOrErr;
 
   StubBufSize = computeSectionStubBufSize(Obj, Section);