config.strictDepsByDefault: init option

so i won't have to change make-derivation.nix when i wan't to make this
true

pkgs/stdenv/generic/make-derivation.nix

@@ -69,7 +69,7 @@ in
 , doInstallCheck ? config.doCheckByDefault or false
 
 , # TODO(@Ericson2314): Make always true and remove
-  strictDeps ? stdenv.hostPlatform != stdenv.buildPlatform
+  strictDeps ? if config.strictDepsByDefault then true else stdenv.hostPlatform != stdenv.buildPlatform
 , meta ? {}
 , passthru ? {}
 , pos ? # position used in error messages and for meta.position

pkgs/top-level/config.nix

@@ -32,6 +32,10 @@ let
       feature = "run <literal>checkPhase</literal> by default";
     };
 
+    strictDepsByDefault = mkMassRebuild {
+      feature = "set <literal>strictDeps</literal> to true by default";
+    };
+
     allowAliases = mkOption {
       type = types.bool;
       default = true;