Remove 2 unused staging flags

Bug: skia:104662
Change-Id: I6f7f4ba8f77a19174b50d8485b3a0c2a5e9a46f7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2340704
Commit-Queue: Adlai Holler <adlai@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
Auto-Submit: Adlai Holler <adlai@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Cr-Commit-Position: refs/heads/master@{#795540}

skia/config/SkUserConfig.h

@@ -231,12 +231,6 @@ SK_API void SkDebugf_FileLine(const char* file,
 // Staging for https://review.skia.org/302290
 #define SK_IMAGE_MAKE_COLOR_TYPE_AND_SPACE_USE_SOURCE_CONTEXT
 
-// Staging for https://review.skia.org/305102
-#define SK_IMAGE_MAKE_FROM_TEXTURE_LEGACY_API
-
-// Staging for https://review.skia.org/306182
-#define SK_IMAGE_MAKE_FROM_ADOPTED_TEXTURE_LEGACY_API
-
 ///////////////////////// Imported from BUILD.gn and skia_common.gypi
 
 /* In some places Skia can use static initializers for global initialization,