Fix precondition/assertion checks

on GS and TypeScript tests.

Refs #1141

Author: reznikmm

source/ada/lsp-ada_document_symbol.adb

@@ -412,6 +412,9 @@ package body LSP.Ada_Document_Symbol is
 
             when Libadalang.Common.Ada_Basic_Decl =>
                for Name of Node.As_Basic_Decl.P_Defining_Names loop
+
+                  exit when Name.Is_Null;
+
                   Append_Name
                     (Name   => Name,
                      Text   => VSS.Strings.To_Virtual_String (Name.Text),

source/ada/lsp-ada_highlighters.adb

@@ -353,6 +353,10 @@ package body LSP.Ada_Highlighters is
 
       Token : Libadalang.Common.Token_Reference := From_Token;
    begin
+      if Libadalang.Common.Is_Trivia (Token) then
+         Token := Libadalang.Common.Next (Token, Exclude_Trivia => True);
+      end if;
+
       --  Scan over all tokens and find a corresponding value in Holder
       while Token < To_Token loop