fix(material/tooltip): Move unthemable tokens to theme mixin (#27569)

Though these tokens are not currently affected by the theme, in the future they will be affected by the design system used for theming (M2 or M3)

BREAKING CHANGE:
There are new styles emitted by mat.tooltip-theme that are not
emitted by any of: mat.tooltip-color, mat.tooltip-typography,
mat.tooltip-density. If you rely on the partial mixins only and don't
call mat.tooltip-theme, you can add mat.tooltip-base to get the
missing styles.

src/material/_index.scss

@@ -183,7 +183,7 @@ legacy-tabs-typography;
 @forward './legacy-tooltip/tooltip-theme' as legacy-tooltip-* show legacy-tooltip-theme,
   legacy-tooltip-color, legacy-tooltip-typography;
 @forward './tooltip/tooltip-theme' as tooltip-* show tooltip-theme, tooltip-color,
-  tooltip-typography, tooltip-density;
+  tooltip-typography, tooltip-density, tooltip-base;
 @forward './tree/tree-theme' as tree-* show tree-theme, tree-color, tree-typography, tree-density;
 
 // MDC Helpers

src/material/tooltip/_tooltip-theme.scss

@@ -1,8 +1,16 @@
 @use '@material/tooltip/plain-tooltip-theme' as mdc-plain-tooltip-theme;
+@use '../core/style/sass-utils';
 @use '../core/theming/theming';
 @use '../core/typography/typography';
 @use '../core/tokens/m2/mdc/plain-tooltip' as m2-mdc-plain-tooltip;
 
+@mixin base($config-or-theme) {
+  // Add default values for tokens not related to color, typography, or density.
+  @include sass-utils.current-selector-or-root() {
+    @include mdc-plain-tooltip-theme.theme(m2-mdc-plain-tooltip.get-unthemable-tokens());
+  }
+}
+
 @mixin color($config-or-theme) {
   $config: theming.get-color-config($config-or-theme);
   $mdc-tooltip-color-tokens: m2-mdc-plain-tooltip.get-color-tokens($config);
@@ -41,6 +49,7 @@
     $density: theming.get-density-config($theme);
     $typography: theming.get-typography-config($theme);
 
+    @include base($theme);
     @if $color != null {
       @include color($color);
     }

src/material/tooltip/tooltip.scss

@@ -13,9 +13,6 @@ $emit-fallback-vars: false) {
   .mat-mdc-tooltip {
     // Add the official slots for the MDC tooltip.
     @include mdc-plain-tooltip-theme.theme-styles($mdc-tooltip-token-slots);
-
-    // Add default values for MDC tooltip tokens that aren't outputted by the theming API.
-    @include mdc-plain-tooltip-theme.theme(m2-mdc-plain-tooltip.get-unthemable-tokens());
   }
 }