[tests] prepare test for inline-stmt-contracts transformation

tests/syntax/inline_stmt_contract.i

+/* run.config
+OPT: -inline-stmt-contracts -print
+*/
+
+int X;
+
+int f() {
+  /*@ requires X == 0;
+      ensures X == 1;
+  */
+  X++;
+  return X;
+}
+
+int g() {
+
+  /*@ behavior b:
+        assumes X >= 0;
+        requires X > -1;
+        ensures X == 0;
+   */
+  if (X >= 0) { X = 0; } else { X = -1; }
+  return X;
+}
+
+int h() {
+  /*@ ensures \false; */
+  return 1;
+}
+
+int i() {
+  /*@ behavior b0:
+        assumes X == 0;
+        ensures X == 1;
+  */
+  X++;
+
+  /*@ behavior b1:
+        assumes X == 1;
+        ensures X == 2;
+  */
+  X++;
+  return X;
+}