[aat] Remove idempotent check

Not necessary after the recent filtering.

Another 10% speedup with LucidaGrande.

src/hb-aat-layout-common.hh

@@ -1034,14 +1034,6 @@ struct StateTableDriver
 	      machine (machine_),
 	      num_glyphs (face_->get_num_glyphs ()) {}
 
-  template <typename context_t>
-  bool is_idempotent_on_all_out_of_bounds (context_t *c, hb_aat_apply_context_t *ac)
-  {
-    const auto entry = machine.get_entry (StateTableT::STATE_START_OF_TEXT, CLASS_OUT_OF_BOUNDS);
-    return !c->table->is_action_initiable (entry) &&
-	    machine.new_state (entry.newState) == StateTableT::STATE_START_OF_TEXT;
-  }
-
   template <typename context_t>
   void drive (context_t *c, hb_aat_apply_context_t *ac)
   {

src/hb-aat-layout-morx-table.hh

@@ -177,8 +177,7 @@ struct RearrangementSubtable
 
     StateTableDriver<Types, EntryData, Flags> driver (machine, c->face);
 
-    if (driver.is_idempotent_on_all_out_of_bounds (&dc, c) &&
-	!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
+    if (!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
     {
       (void) c->buffer->message (c->font, "skipped chainsubtable because no glyph matches");
       return_trace (false);
@@ -348,8 +347,7 @@ struct ContextualSubtable
 
     StateTableDriver<Types, EntryData, Flags> driver (machine, c->face);
 
-    if (driver.is_idempotent_on_all_out_of_bounds (&dc, c) &&
-	!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
+    if (!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
     {
       (void) c->buffer->message (c->font, "skipped chainsubtable because no glyph matches");
       return_trace (false);
@@ -625,8 +623,7 @@ struct LigatureSubtable
 
     StateTableDriver<Types, EntryData, Flags> driver (machine, c->face);
 
-    if (driver.is_idempotent_on_all_out_of_bounds (&dc, c) &&
-	!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
+    if (!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
     {
       (void) c->buffer->message (c->font, "skipped chainsubtable because no glyph matches");
       return_trace (false);
@@ -920,8 +917,7 @@ struct InsertionSubtable
 
     StateTableDriver<Types, EntryData, Flags> driver (machine, c->face);
 
-    if (driver.is_idempotent_on_all_out_of_bounds (&dc, c) &&
-	!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
+    if (!c->buffer_glyph_set.may_intersect (*c->machine_glyph_set))
     {
       (void) c->buffer->message (c->font, "skipped chainsubtable because no glyph matches");
       return_trace (false);