Revert "experimental keyboard height fix"

This reverts commit c2c7cc0729.

apps/weblibre/lib/features/geckoview/features/browser/presentation/screens/browser.dart

@@ -1265,6 +1265,8 @@ class BrowserScreen extends HookConsumerWidget {
 
     // Get pixel ratio for converting logical pixels to physical pixels
     final pixelRatio = MediaQuery.of(context).devicePixelRatio;
+    final bottomSystemInsetPx =
+        (MediaQuery.viewPaddingOf(context).bottom * pixelRatio).round();
 
     // Watch find-in-page visibility for the selected tab
     final findInPageVisible =
@@ -1303,34 +1305,39 @@ class BrowserScreen extends HookConsumerWidget {
         : 0.0;
     final stableToolbarHeightPx = (stableToolbarHeight * pixelRatio).round();
 
-    final keyboardVisibleState = useState(false);
+    // Compute toolbar visibility for keyboard inset math.
+    // Uses ref.watch via the toolbarDismissed useState to avoid
+    // subscribing to every hide/show toggle.
+    final toolbarVisibleForLayout =
+        sheetDisplayed || (!tabInFullScreen && !toolbarDismissed.value);
+
+    final keyboardHeightPx = useState<int?>(null);
 
     useOnStreamChange(
       viewportService.keyboardEvents,
       onData: (event) {
         if (!event.isAnimating) {
-          keyboardVisibleState.value = event.isVisible;
+          final nextKeyboardHeightPx = event.isVisible
+              ? event.heightPx + bottomSystemInsetPx
+              : null;
+          if (keyboardHeightPx.value != nextKeyboardHeightPx) {
+            keyboardHeightPx.value = nextKeyboardHeightPx;
+          }
         }
       },
     );
 
-    final keyboardVisible = keyboardVisibleState.value;
+    final keyboardVisible = keyboardHeightPx.value != null;
+
+    final bottomLayoutReservedPx = (!autoHideTabBar && toolbarVisibleForLayout)
+        ? (bottomAppBarTotalHeight * pixelRatio).round()
+        : 0;
+    final keyboardViewportHeightPx = keyboardVisible
+        ? math.max(0, keyboardHeightPx.value! - bottomLayoutReservedPx)
+        : 0;
 
-    // While the keyboard is up, report only the chrome that lifts itself above
-    // it. Gecko already insets its visual viewport for the IME on its own, so
-    // encoding the keyboard as dynamic toolbar chrome double-counts the bottom
-    // occlusion and leaves fixed-bottom page content cut off.
-    //
-    // The find-in-page bar anchors at max(toolbar, viewInsets.bottom), i.e. it
-    // floats above the keyboard over visible page content, so it must be
-    // reported. The bottom toolbar (Layer 2) is Positioned(bottom: 0) with no
-    // viewInsets handling and the scaffold is resizeToAvoidBottomInset: false,
-    // so it stays *behind* the keyboard even when force-shown (e.g. via
-    // showToolbarAsExpanded on form focus) and must not be reported. If Layer 2
-    // ever gains keyboard-clearing offsets, stableToolbarHeightPx has to be
-    // added back here.
     final effectiveToolbarHeightPx = keyboardVisible
-        ? findInPageHeightPx
+        ? keyboardViewportHeightPx + findInPageHeightPx
         : stableToolbarHeightPx;
 
     final lastToolbarMaxHeightPx = useRef<int?>(null);