Update patch context in filament-allow-clang-windows.patch.

PiperOrigin-RevId: 952161543
Change-Id: Ia832f692f1f42e905a6cf66365731d5714297db9

cmake/filament-allow-clang-windows.patch

@@ -1,7 +1,20 @@
 diff --git a/CMakeLists.txt b/CMakeLists.txt
-index e5475ef5..4eb8a68b 100644
 --- a/CMakeLists.txt
 +++ b/CMakeLists.txt
+@@ -11,12 +11,7 @@ cmake_minimum_required(VERSION 3.22.1)
+ # Unsupported environment
+ # ==================================================================================================
+ 
+-# Filament does not support MSYS2-based environment on Windows. See issue #9968.
+-if(DEFINED ENV{MSYSTEM})
+-    message(FATAL_ERROR
+-        "MSYS2 Subsystem detected($ENV{MSYSTEM}). "
+-        "Filament does not support MSYS2-based environment on Windows.")
+-endif()
++
+ 
+ # ==================================================================================================
+ # Toolchain configuration
 @@ -247,57 +247,59 @@ if (WIN32)
      # __declspec(dllexport) in front of each functions).
      set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS ON)
@@ -492,17 +505,6 @@ diff --git a/filament/CMakeLists.txt b/filament/CMakeLists.txt
 +    endif()
  endif()
 
-diff --git a/filament/backend/CMakeLists.txt b/filament/backend/CMakeLists.txt
---- a/filament/backend/CMakeLists.txt
-+++ b/filament/backend/CMakeLists.txt
-@@ -525,3 +525,7 @@
- endif()
- 
-+if (WIN32 AND CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
-+    list(APPEND FILAMENT_WARNINGS -Wno-error=cast-function-type-mismatch -Wno-error=unused-variable -Wno-error=microsoft-unqualified-friend)
-+endif()
-+
- if (APPLE)
 
 diff --git a/libs/utils/include/utils/compiler.h b/libs/utils/include/utils/compiler.h
 --- a/libs/utils/include/utils/compiler.h
@@ -517,3 +519,18 @@ diff --git a/libs/utils/include/utils/compiler.h b/libs/utils/include/utils/comp
  #else
  #define UTILS_THREAD_ANNOTATION_ATTRIBUTE(x)
 
+diff --git a/filament/backend/CMakeLists.txt b/filament/backend/CMakeLists.txt
+index 78c05dd22..b124685c4 100644
+--- a/filament/backend/CMakeLists.txt
++++ b/filament/backend/CMakeLists.txt
+@@ -523,6 +523,9 @@ else()
+             -Wover-aligned -Wreorder-init-list
+             -Werror
+     )
++    if (WIN32 AND CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
++        list(APPEND FILAMENT_WARNINGS -Wno-error=cast-function-type-mismatch -Wno-error=unused-variable -Wno-error=microsoft-unqualified-friend)
++    endif()
+ endif()
+
+ if (APPLE)
+