Add MemberAccessorExpression tests

This CL adds unit tests for the MemberArrayExpression.

Bug: tint:11
Change-Id: I790d27018b516b3b2b79b6ed892c1a0e00b65818
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/16681
Reviewed-by: Sarah Mashayekhi <sarahmashay@google.com>
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index f4ef8b3..d58e85e 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -222,6 +222,7 @@
   ast/kill_statement_test.cc
   ast/location_decoration_test.cc
   ast/loop_statement_test.cc
+  ast/member_accessor_expression_test.cc
   ast/module_test.cc
   ast/set_decoration_test.cc
   ast/struct_member_test.cc