Clang: Locator filter for the symbol database

There are no symbol queries for the locator filters. The signature
generation is still not implemented but for simple cases it should work.

Change-Id: Ic6b04fbe1e7e057892f194ac139615c47d6ec33f
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/libs/utils/sizedarray.h

@@ -54,6 +54,13 @@ public:
     using std::array<T, MaxSize>::rend;
     using std::array<T, MaxSize>::crend;
 
+    constexpr SizedArray() = default;
+    constexpr SizedArray(std::initializer_list<T> list)
+        : m_size(list.size())
+    {
+        std::copy(list.begin(), list.end(), begin());
+    }
+
     constexpr size_type size() const
     {
         return m_size;