[clang] [clang][dataflow] Fully support Environment construction for Stmt analysis. (PR #91616)

[Samira Bazuzi via cfe-commits]

================
@@ -403,4 +405,35 @@ TEST_F(EnvironmentTest,
               Contains(Member));
 }
 
+TEST_F(EnvironmentTest, Stmt) {
+  using namespace ast_matchers;
+
+  std::string Code = R"cc(
+      struct S {int i;};
+      void foo() {
+        S AnS = S{1};
+      }
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bazuzi wrote:

A variable declaration outside a function doesn't actually exist within a Stmt, nor is it a Stmt.

In order to analyze a global variable declaration, one option is to synthesize a DeclStmt that holds the VarDecl. I was trying to keep this test simple, but could add an additional test for this synthesis pattern?

https://github.com/llvm/llvm-project/pull/91616