Implement internal functions in storage.

test/libsolidity/semanticTests/array/copying/copy_internal_function_array_to_storage.sol

@@ -17,6 +17,8 @@ contract C {
     }
 }
 
+// ====
+// compileViaYul: also
 // ----
 // one() -> 3
 // two() -> FAILURE

test/libsolidity/semanticTests/array/inline_array_strings_from_document.sol

@@ -5,6 +5,8 @@ contract C {
     }
 }
 
+// ====
+// compileViaYul: also
 // ----
 // f(uint256): 0 -> 0x20, 0x4, "This"
 // f(uint256): 1 -> 0x20, 0x2, "is"