Use SmallVectorImpl& for function arguments instead of SmallVector.

include/clang/Driver/Types.h

include/clang/Parse/Parser.h

include/clang/Sema/DeclSpec.h

include/clang/Sema/Sema.h

include/clang/Serialization/ASTReader.h

lib/AST/ASTDiagnostic.cpp

lib/AST/VTableBuilder.cpp

lib/CodeGen/CGCall.cpp

lib/CodeGen/CGExpr.cpp

lib/CodeGen/CodeGenFunction.h

lib/CodeGen/TargetInfo.cpp

lib/Driver/Types.cpp

lib/Frontend/ChainedIncludesSource.cpp

lib/Lex/TokenLexer.cpp

lib/Parse/ParseDecl.cpp

lib/Rewrite/Frontend/RewriteModernObjC.cpp

lib/Rewrite/Frontend/RewriteObjC.cpp

lib/Sema/SemaDecl.cpp

lib/Sema/SemaDeclAttr.cpp

lib/Sema/SemaExpr.cpp