[Impeller] deleted the old blur (#50470)

fixes flutter/flutter#131579


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Author: gaaclarke

ci/licenses_golden/excluded_files

@@ -144,7 +144,6 @@
 ../../../flutter/impeller/docs
 ../../../flutter/impeller/entity/contents/checkerboard_contents_unittests.cc
 ../../../flutter/impeller/entity/contents/content_context_unittests.cc
-../../../flutter/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents_unittests.cc
 ../../../flutter/impeller/entity/contents/filters/gaussian_blur_filter_contents_unittests.cc
 ../../../flutter/impeller/entity/contents/filters/inputs/filter_input_unittests.cc
 ../../../flutter/impeller/entity/contents/host_buffer_unittests.cc

ci/licenses_golden/licenses_flutter

@@ -5102,8 +5102,6 @@ ORIGIN: ../../../flutter/impeller/entity/contents/filters/color_filter_contents.
 ORIGIN: ../../../flutter/impeller/entity/contents/filters/color_filter_contents.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/contents/filters/color_matrix_filter_contents.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/contents/filters/color_matrix_filter_contents.h + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.cc + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/contents/filters/filter_contents.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/contents/filters/filter_contents.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/contents/filters/gaussian_blur_filter_contents.cc + ../../../flutter/LICENSE
@@ -7935,8 +7933,6 @@ FILE: ../../../flutter/impeller/entity/contents/filters/color_filter_contents.cc
 FILE: ../../../flutter/impeller/entity/contents/filters/color_filter_contents.h
 FILE: ../../../flutter/impeller/entity/contents/filters/color_matrix_filter_contents.cc
 FILE: ../../../flutter/impeller/entity/contents/filters/color_matrix_filter_contents.h
-FILE: ../../../flutter/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.cc
-FILE: ../../../flutter/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.h
 FILE: ../../../flutter/impeller/entity/contents/filters/filter_contents.cc
 FILE: ../../../flutter/impeller/entity/contents/filters/filter_contents.h
 FILE: ../../../flutter/impeller/entity/contents/filters/gaussian_blur_filter_contents.cc

impeller/entity/BUILD.gn

@@ -134,8 +134,6 @@ impeller_component("entity") {
     "contents/filters/color_filter_contents.h",
     "contents/filters/color_matrix_filter_contents.cc",
     "contents/filters/color_matrix_filter_contents.h",
-    "contents/filters/directional_gaussian_blur_filter_contents.cc",
-    "contents/filters/directional_gaussian_blur_filter_contents.h",
     "contents/filters/filter_contents.cc",
     "contents/filters/filter_contents.h",
     "contents/filters/gaussian_blur_filter_contents.cc",
@@ -268,7 +266,6 @@ impeller_component("entity_unittests") {
   sources = [
     "contents/checkerboard_contents_unittests.cc",
     "contents/content_context_unittests.cc",
-    "contents/filters/directional_gaussian_blur_filter_contents_unittests.cc",
     "contents/filters/gaussian_blur_filter_contents_unittests.cc",
     "contents/filters/inputs/filter_input_unittests.cc",
     "contents/host_buffer_unittests.cc",