wear_ui: Remove kMaxCols/kMaxRows/visible_text_rows/menu_headers_.

We've deprecated kMaxCols/kMaxRows in ScreenRecoveryUI since commit
aa0d6afb61f4cf928e87c7a21bcb59fc973f15a0. They unnecessarily limit the
screen size to 96x96 characters.

Also remove the recomputations of text_cols, visible_text_rows (which is
the same as text_rows_). Remove the unintentional hiding of menu_headers_.

Test: mmma bootable/recovery
Change-Id: I7d1526b651943312d62d52cd200414b42bf9b12a
diff --git a/wear_ui.cpp b/wear_ui.cpp
index 169ef20..71a5351 100644
--- a/wear_ui.cpp
+++ b/wear_ui.cpp
@@ -191,20 +191,6 @@
   gr_flip();
 }
 
-bool WearRecoveryUI::InitTextParams() {
-  if (!ScreenRecoveryUI::InitTextParams()) {
-    return false;
-  }
-
-  text_cols_ = (gr_fb_width() - (kMarginWidth * 2)) / char_width_;
-
-  if (text_rows_ > kMaxRows) text_rows_ = kMaxRows;
-  if (text_cols_ > kMaxCols) text_cols_ = kMaxCols;
-
-  visible_text_rows = (gr_fb_height() - (kMarginHeight * 2)) / char_height_;
-  return true;
-}
-
 bool WearRecoveryUI::Init(const std::string& locale) {
   if (!ScreenRecoveryUI::Init(locale)) {
     return false;
@@ -269,7 +255,7 @@
     show_menu = true;
     menu_sel = initial_selection;
     menu_start = 0;
-    menu_end = visible_text_rows - 1 - kMenuUnusableRows;
+    menu_end = text_rows_ - 1 - kMenuUnusableRows;
     if (menu_items <= menu_end) menu_end = menu_items;
     update_screen_locked();
   }