Cast void* to JniContext* using static_cast.

static_cast is more appropriate than reinrerpret_cast for casting from
void* to JniContext*. See Section 7.2.1 (page 173) in The C++
Programming Language, 4th Edition and
https://stackoverflow.com/questions/310451/should-i-use-static-cast-or-reinterpret-cast-when-casting-a-void-to-whatever

PiperOrigin-RevId: 293812940

extensions/av1/src/main/jni/gav1_jni.cc

@@ -403,8 +403,7 @@ int Libgav1GetFrameBuffer(void* callback_private_data, int bitdepth,
     return -1;
     return -1;
   }
   }
 
 
-  JniContext* const context =
-      reinterpret_cast<JniContext*>(callback_private_data);
+  JniContext* const context = static_cast<JniContext*>(callback_private_data);
   JniFrameBuffer* jni_buffer;
   JniFrameBuffer* jni_buffer;
   context->jni_status_code = context->buffer_manager.GetBuffer(
   context->jni_status_code = context->buffer_manager.GetBuffer(
       static_cast<size_t>(y_plane_size), static_cast<size_t>(uv_plane_size),
       static_cast<size_t>(y_plane_size), static_cast<size_t>(uv_plane_size),
@@ -443,8 +442,7 @@ int Libgav1GetFrameBuffer(void* callback_private_data, int bitdepth,
 
 
 void Libgav1ReleaseFrameBuffer(void* callback_private_data,
 void Libgav1ReleaseFrameBuffer(void* callback_private_data,
                                void* buffer_private_data) {
                                void* buffer_private_data) {
-  JniContext* const context =
-      reinterpret_cast<JniContext*>(callback_private_data);
+  JniContext* const context = static_cast<JniContext*>(callback_private_data);
   const int buffer_id = reinterpret_cast<int>(buffer_private_data);
   const int buffer_id = reinterpret_cast<int>(buffer_private_data);
   context->jni_status_code = context->buffer_manager.ReleaseBuffer(buffer_id);
   context->jni_status_code = context->buffer_manager.ReleaseBuffer(buffer_id);
   if (context->jni_status_code != kJniStatusOk) {
   if (context->jni_status_code != kJniStatusOk) {