Avoid an explicit static_cast

...when shoehorning a std::size_t value into sal_Int32, to not suppress
potential warnings from tools like -fsanitize=implicit-signed-integer-truncation
and -fsanitize=implicit-integer-sign-change

Change-Id: I610410f7cd69769c3721b2019e16b4c9f214ad81
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/142407
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
diff --git a/include/rtl/ustring.hxx b/include/rtl/ustring.hxx
index d7d529f..16ccece 100644
--- a/include/rtl/ustring.hxx
+++ b/include/rtl/ustring.hxx
@@ -163,7 +163,7 @@ public:
    /**
      make it easier to pass to OUStringBuffer and similar without casting/converting
    */
    constexpr std::u16string_view asView() const { return {pData->buffer, static_cast<sal_uInt32>(pData->length)}; }
    constexpr std::u16string_view asView() const { return std::u16string_view(pData->buffer, pData->length); }

    inline operator const OUString&() const;