Switch to ssize_t from size_t to unbreak windows builders.

Builders that have -fms-compatibility on by default define size_t implicitly.
Tests that provide conflicting definitions would cause unintended failures.

llvm-svn: 199195
diff --git a/clang/unittests/AST/DeclPrinterTest.cpp b/clang/unittests/AST/DeclPrinterTest.cpp
index 44fa742..33c5136 100644
--- a/clang/unittests/AST/DeclPrinterTest.cpp
+++ b/clang/unittests/AST/DeclPrinterTest.cpp
@@ -370,11 +370,11 @@
 
 TEST(DeclPrinter, TestFunctionDecl11) {
   ASSERT_TRUE(PrintedDeclCXX98Matches(
-    "typedef long size_t;"
+    "typedef long ssize_t;"
     "typedef int *pInt;"
-    "void A(int a, pInt b, size_t c);",
+    "void A(int a, pInt b, ssize_t c);",
     "A",
-    "void A(int a, pInt b, size_t c)"));
+    "void A(int a, pInt b, ssize_t c)"));
     // Should be: with semicolon
 }