Add timeline events for post frame callbacks (flutter#136435)

Before this change, long-running post-frame callbacks wouldn't show up in the timeline at all.  This adds a timeline event for post-frame callbacks, with a debug flag that will add timeline events for each individual callback.

#testexempt -- we have no way to test calls to the timeline.

Author: tvolkert

packages/flutter/lib/src/cupertino/context_menu.dart

@@ -585,7 +585,7 @@ class _CupertinoContextMenuState extends State<CupertinoContextMenu> with Ticker
           _lastOverlayEntry?.dispose();
           _lastOverlayEntry = null;
           _openController.reset();
-        });
+        }, debugLabel: 'removeContextMenuDecoy');
 
       case AnimationStatus.forward:
       case AnimationStatus.reverse:
@@ -1009,7 +1009,7 @@ class _ContextMenuRoute<T> extends PopupRoute<T> {
       _updateTweenRects();
       _internalOffstage = false;
       _setOffstageInternally();
-    });
+    }, debugLabel: 'renderContextMenuRouteOffstage');
     return super.didPush();
   }
 

packages/flutter/lib/src/cupertino/date_picker.dart

@@ -1007,7 +1007,7 @@ class _CupertinoDatePickerDateTimeState extends State<CupertinoDatePicker> {
         final int position = minCheck ? positionDouble.ceil() : positionDouble.floor();
         _animateColumnControllerToItem(minuteController, position);
       }
-    });
+    }, debugLabel: 'DatePicker.scrollToDate');
   }
 
   @override
@@ -1401,7 +1401,7 @@ class _CupertinoDatePickerDateState extends State<CupertinoDatePicker> {
       if (selectedDay != newDate.day) {
         _animateColumnControllerToItem(dayController, newDate.day - 1);
       }
-    });
+    }, debugLabel: 'DatePicker.scrollToDate');
   }
 
   @override
@@ -1725,7 +1725,7 @@ class _CupertinoDatePickerMonthYearState extends State<CupertinoDatePicker> {
       if (selectedMonth != newDate.month) {
         _animateColumnControllerToItem(monthController, newDate.month - 1);
       }
-    });
+    }, debugLabel: 'DatePicker.scrollToDate');
   }
 
   @override

packages/flutter/lib/src/cupertino/refresh.dart

@@ -461,7 +461,7 @@ class _CupertinoSliverRefreshControlState extends State<CupertinoSliverRefreshCo
       } else {
         SchedulerBinding.instance.addPostFrameCallback((Duration timestamp) {
           setState(() => hasSliverLayoutExtent = false);
-        });
+        }, debugLabel: 'Refresh.goToDone');
       }
     }
 
@@ -497,7 +497,7 @@ class _CupertinoSliverRefreshControlState extends State<CupertinoSliverRefreshCo
                 }
               });
               setState(() => hasSliverLayoutExtent = true);
-            });
+            }, debugLabel: 'Refresh.transition');
           }
           return RefreshIndicatorMode.armed;
         }

packages/flutter/lib/src/cupertino/spell_check_suggestions_toolbar.dart

@@ -130,7 +130,7 @@ class CupertinoSpellCheckSuggestionsToolbar extends StatelessWidget {
       if (editableTextState.mounted) {
         editableTextState.bringIntoView(editableTextState.textEditingValue.selection.extent);
       }
-    });
+    }, debugLabel: 'SpellCheckSuggestions.bringIntoView');
     editableTextState.hideToolbar();
   }
 

packages/flutter/lib/src/gestures/binding.dart

@@ -175,7 +175,7 @@ class _Resampler {
         _timer = Timer.periodic(_samplingInterval, (_) => _onSampleTimeChanged());
         // Trigger an immediate sample time change.
         _onSampleTimeChanged();
-      });
+      }, debugLabel: 'Resampler.startTimer');
     }
   }
 

packages/flutter/lib/src/material/autocomplete.dart

@@ -201,7 +201,7 @@ class _AutocompleteOptions<T extends Object> extends StatelessWidget {
                     if (highlight) {
                       SchedulerBinding.instance.addPostFrameCallback((Duration timeStamp) {
                         Scrollable.ensureVisible(context, alignment: 0.5);
-                      });
+                      }, debugLabel: 'AutocompleteOptions.ensureVisible');
                     }
                     return Container(
                       color: highlight ? Theme.of(context).focusColor : null,

packages/flutter/lib/src/material/dropdown_menu.dart

@@ -423,7 +423,7 @@ class _DropdownMenuState<T> extends State<DropdownMenu<T>> {
       setState(() {
         leadingPadding = getWidth(_leadingKey);
       });
-    });
+    }, debugLabel: 'DropdownMenu.refreshLeadingPadding');
   }
 
   void scrollToHighlight() {
@@ -432,7 +432,7 @@ class _DropdownMenuState<T> extends State<DropdownMenu<T>> {
       if (highlightContext != null) {
         Scrollable.ensureVisible(highlightContext);
       }
-    });
+    }, debugLabel: 'DropdownMenu.scrollToHighlight');
   }
 
   double? getWidth(GlobalKey key) {

packages/flutter/lib/src/material/input_date_picker_form_field.dart

@@ -174,7 +174,7 @@ class _InputDatePickerFormFieldState extends State<InputDatePickerFormField> {
           _selectedDate = widget.initialDate;
           _updateValueForSelectedDate();
         });
-      });
+      }, debugLabel: 'InputDatePickerFormField.update');
     }
   }
 

packages/flutter/lib/src/material/menu_anchor.dart

@@ -583,7 +583,7 @@ _MenuAnchorState? get _previousFocusableSibling {
     } else if (!inDispose) {
       SchedulerBinding.instance.addPostFrameCallback((_) {
         _overlayController.hide();
-      });
+      }, debugLabel: 'MenuAnchor.hide');
     }
     if (!inDispose) {
       // Notify that _childIsOpen changed state, but only if not
@@ -1150,7 +1150,7 @@ class _MenuItemButtonState extends State<MenuItemButton> {
     SchedulerBinding.instance.addPostFrameCallback((Duration _) {
       FocusManager.instance.applyFocusChangesIfNeeded();
       widget.onPressed?.call();
-    });
+    }, debugLabel: 'MenuAnchor.onPressed');
   }
 
   void _createInternalFocusNodeIfNeeded() {
@@ -1902,7 +1902,7 @@ class _SubmenuButtonState extends State<SubmenuButton> {
           SchedulerBinding.instance.addPostFrameCallback((_) {
             _menuController._anchor?._focusButton();
             _waitingToFocusMenu = false;
-          });
+          }, debugLabel: 'MenuAnchor.focus');
           _waitingToFocusMenu = true;
         }
         setState(() { /* Rebuild with updated controller.isOpen value */ });

packages/flutter/lib/src/material/spell_check_suggestions_toolbar.dart

@@ -142,7 +142,7 @@ class SpellCheckSuggestionsToolbar extends StatelessWidget {
       if (editableTextState.mounted) {
         editableTextState.bringIntoView(editableTextState.textEditingValue.selection.extent);
       }
-    });
+    }, debugLabel: 'SpellCheckerSuggestionsToolbar.bringIntoView');
     editableTextState.hideToolbar();
   }