Fix some handling of AST nodes with diagnostics.

The diagnostic system for Clang can already handle many AST nodes.  Instead
of converting them to strings first, just hand the AST node directly to
the diagnostic system and let it handle the output.  Minor changes in some
diagnostic output.

llvm-svn: 328688
diff --git a/clang/test/SemaCUDA/kernel-call.cu b/clang/test/SemaCUDA/kernel-call.cu
index 47d7762..b2433c9 100644
--- a/clang/test/SemaCUDA/kernel-call.cu
+++ b/clang/test/SemaCUDA/kernel-call.cu
@@ -13,13 +13,13 @@
 
 int main(void) {
   g1<<<1, 1>>>(42);
-  g1(42); // expected-error {{call to global function g1 not configured}}
+  g1(42); // expected-error {{call to global function 'g1' not configured}}
   g1<<<1>>>(42); // expected-error {{too few execution configuration arguments to kernel function call}}
   g1<<<1, 1, 0, 0, 0>>>(42); // expected-error {{too many execution configuration arguments to kernel function call}}
 
   t1(1);
 
-  h1<<<1, 1>>>(42); // expected-error {{kernel call to non-global function h1}}
+  h1<<<1, 1>>>(42); // expected-error {{kernel call to non-global function 'h1'}}
 
   int (*fp)(int) = h2;
   fp<<<1, 1>>>(42); // expected-error {{must have void return type}}