[NFC][llvm-objcopy] Cleanup namespace usage in llvm-objcopy.

[plotfi]

Summary

Nest any classes not used outside of a file into anon. Nest any classes used across files in llvm-objcopy into namespace llvm::objcopy.

[jakehehrlich]

Seems pretty non-objectionable to me. LGTM

[jakehehrlich]

Uh...I mean.."unobjectionable"...don't judge me.

[alexander-shaposhnikov]

LG, thanks

tools/llvm-objcopy/Object.h

 #include <vector>
 
 namespace llvm {
+namespace objcopy {
 
 class Buffer;
 class SectionBase;

     return *Segments.back();
   }
 };
+} // end namespace objcopy
 } // end namespace llvm
 
 #endif // LLVM_TOOLS_OBJCOPY_OBJECT_H

tools/llvm-objcopy/Object.cpp

 #include <vector>
 
 using namespace llvm;
+using namespace llvm::objcopy;
 using namespace object;
 using namespace ELF;
 

 }
 
 namespace llvm {
+namespace objcopy {
 
 template class ELFBuilder<ELF64LE>;
 template class ELFBuilder<ELF64BE>;

 template class ELFWriter<ELF64BE>;
 template class ELFWriter<ELF32LE>;
 template class ELFWriter<ELF32BE>;
+} // end namespace objcopy
 } // end namespace llvm

tools/llvm-objcopy/llvm-objcopy.h

 #include <string>
 
 namespace llvm {
+namespace objcopy {
 
 LLVM_ATTRIBUTE_NORETURN extern void error(Twine Message);
 LLVM_ATTRIBUTE_NORETURN extern void reportError(StringRef File, Error E);

   error(Buf);
 }
 
+} // end namespace objcopy
 } // end namespace llvm
 
 #endif // LLVM_TOOLS_OBJCOPY_OBJCOPY_H

tools/llvm-objcopy/llvm-objcopy.cpp

 #include <utility>
 
 using namespace llvm;
+using namespace llvm::objcopy;
 using namespace object;
 using namespace ELF;
 

   StripOptTable() : OptTable(StripInfoTable, true) {}
 };
 
-} // namespace
-
-// The name this program was invoked as.
-static StringRef ToolName;
-
-namespace llvm {
-
-LLVM_ATTRIBUTE_NORETURN void error(Twine Message) {
-  errs() << ToolName << ": " << Message << ".\n";
-  errs().flush();
-  exit(1);
-}
-
-LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, std::error_code EC) {
-  assert(EC);
-  errs() << ToolName << ": '" << File << "': " << EC.message() << ".\n";
-  exit(1);
-}
-
-LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, Error E) {
-  assert(E);
-  std::string Buf;
-  raw_string_ostream OS(Buf);
-  logAllUnhandledErrors(std::move(E), OS, "");
-  OS.flush();
-  errs() << ToolName << ": '" << File << "': " << Buf;
-  exit(1);
-}
-
 struct CopyConfig {
   StringRef OutputFilename;
   StringRef InputFilename;

 
 using SectionPred = std::function<bool(const SectionBase &Sec)>;
 
+} // namespace
+
+namespace llvm {
+namespace objcopy {
+
+// The name this program was invoked as.
+StringRef ToolName;
+
+LLVM_ATTRIBUTE_NORETURN void error(Twine Message) {
+  errs() << ToolName << ": " << Message << ".\n";
+  errs().flush();
+  exit(1);
+}
+
+LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, std::error_code EC) {
+  assert(EC);
+  errs() << ToolName << ": '" << File << "': " << EC.message() << ".\n";
+  exit(1);
+}
+
+LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, Error E) {
+  assert(E);
+  std::string Buf;
+  raw_string_ostream OS(Buf);
+  logAllUnhandledErrors(std::move(E), OS, "");
+  OS.flush();
+  errs() << ToolName << ": '" << File << "': " << Buf;
+  exit(1);
+}
+
+} // end namespace objcopy
 } // end namespace llvm
 
 static bool IsDWOSection(const SectionBase &Sec) {