Revert "Merge pull request python-pillow#7311 from k128/main"

This reverts commit 39d866b, reversing
changes made to f39f74f.

Author: radarhere

Tests/test_file_webp.py

@@ -233,4 +233,5 @@ def test_duration(self, tmp_path):
             im.save(out_webp, save_all=True)
 
         with Image.open(out_webp) as reloaded:
+            reloaded.load()
             assert reloaded.info["duration"] == 1000

src/PIL/WebPImagePlugin.py

@@ -74,9 +74,6 @@ def _open(self):
         self.info["background"] = (bg_r, bg_g, bg_b, bg_a)
         self.n_frames = frame_count
         self.is_animated = self.n_frames > 1
-        ret = self._decoder.get_next()
-        if ret is not None:
-            self.info["duration"] = ret[1]
         self._mode = "RGB" if mode == "RGBX" else mode
         self.rawmode = mode
         self.tile = []
@@ -93,7 +90,7 @@ def _open(self):
             self.info["xmp"] = xmp
 
         # Initialize seek state
-        self._reset()
+        self._reset(reset=False)
 
     def _getexif(self):
         if "exif" not in self.info:
@@ -116,8 +113,9 @@ def seek(self, frame):
         # Set logical frame to requested position
         self.__logical_frame = frame
 
-    def _reset(self):
-        self._decoder.reset()
+    def _reset(self, reset=True):
+        if reset:
+            self._decoder.reset()
         self.__physical_frame = 0
         self.__loaded = -1
         self.__timestamp = 0