[vala] Created tag 0.51.91

[Rico Tzschichholz <ricotz src gnome org>]

The signed tag '0.51.91' was created.

Tagger: Rico Tzschichholz <ricotz ubuntu com>
Date: 1615399323 +0100

    0.51.91

Changes since the last tag '0.51.90':

Rico Tzschichholz (17):
      vala: Add missing null-check in DataType.get_type_signature()
      glib-2.0: Add some missing type-arguments
      gio-2.0: Add some missing type-arguments
      vala: Move type-argument/-parameter count check to DataType.check_type_arguments()
      vala: Check array type of declarations for errornous type-arguments
      vala: Check (optional) type-arguments of array creation expression
      codegen: Report error for missing type-arguments of HashTable (de)serialization
      codegen: Free intermediate temp-variables of postcondition expression
      codegen: Use the one available source_reference for internal error
      codegen: Fix access to captured generics in async method of interfaces
      tests: Add "string concat" test for POSIX to increase coverage
      codegen: Don't ever create null-aware free macro for GenericType
      codegen: Don't add generics arguments/parameters to async finish method
      codegen: Drop inner casts before converting between generics and integers
      vala: Replace all type parameter occurances in parameters for signal delegate
      vapi: Update GIR-based bindings
      Release 0.51.91