Handle char array initialization through { string literal } (Cpp2Rust#175)

`const char var[] = {"string literal"}` is a valid initialization. Add
support for it in codegen.

Author: lucic71

cpp2rust/converter/converter.cpp

@@ -2795,6 +2795,10 @@ bool Converter::VisitInitListExpr(clang::InitListExpr *expr) {
       StrCat(token::kComma);
     }
   } else {
+    if (IsInitExprOfStringLiteral(expr)) {
+      Convert(expr->getInit(0)->IgnoreParenImpCasts());
+      return false;
+    }
     PushBracket bracket(*this);
     for (auto *init : expr->inits()) {
       ConvertVarInit(init->getType(), init);

tests/unit/out/refcount/string_literals.rs

@@ -60,5 +60,12 @@ fn main_0() -> i32 {
         let _str: Ptr<u8> = (immutable_empty_arr.as_pointer() as Ptr<u8>);
         foo_const_1(_str)
     });
+    let inited_through_init_list: Value<Box<[u8]>> = Rc::new(RefCell::new(Box::<[u8]>::from(
+        b"papanasi cu smantana\0".as_slice(),
+    )));
+    ({
+        let _str: Ptr<u8> = (inited_through_init_list.as_pointer() as Ptr<u8>);
+        foo_const_1(_str)
+    });
     return 0;
 }

tests/unit/out/refcount/string_literals_c.rs

@@ -91,5 +91,12 @@ fn main_0() -> i32 {
         let _str: Ptr<u8> = (immutable_empty_arr.as_pointer() as Ptr<u8>);
         foo_const_1(_str)
     });
+    let inited_through_init_list: Value<Box<[u8]>> = Rc::new(RefCell::new(Box::<[u8]>::from(
+        b"papanasi cu smantana\0".as_slice(),
+    )));
+    ({
+        let _str: Ptr<u8> = (inited_through_init_list.as_pointer() as Ptr<u8>);
+        foo_const_1(_str)
+    });
     return 0;
 }