pw_assert: Remove the deprecated light.h header

Bug: 350
Change-Id: I35f37a3d102eb96dde2e8bf0a92acffc52153711
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/38741
Pigweed-Auto-Submit: Wyatt Hepler <hepler@google.com>
Commit-Queue: Wyatt Hepler <hepler@google.com>
Reviewed-by: Keir Mierle <keir@google.com>
diff --git a/pw_assert/BUILD b/pw_assert/BUILD
index 58ce601..09a5929 100644
--- a/pw_assert/BUILD
+++ b/pw_assert/BUILD
@@ -31,7 +31,6 @@
         "public/pw_assert/assert.h",
         "public/pw_assert/check.h",
         "public/pw_assert/internal/check_impl.h",
-        "public/pw_assert/light.h",
         "public/pw_assert/options.h",
         "public/pw_assert/short.h",
     ],
diff --git a/pw_assert/BUILD.gn b/pw_assert/BUILD.gn
index 5e83da1..40b1635 100644
--- a/pw_assert/BUILD.gn
+++ b/pw_assert/BUILD.gn
@@ -41,14 +41,9 @@
     # Also expose assert.h to all users of pw_assert.
     ":light",
   ]
-
-  # TODO(pwbug/350): Allow assert.h to include check.h for backwards
-  #     compatibility. Remove this when projects have migrated.
-  allow_circular_includes_from = [ ":light" ]
-  deps = [ ":light" ]
 }
 
-# Provide a way include "pw_assert/light.h" without depending on the full
+# Provide a way include "pw_assert/assert.h" without depending on the full
 # assert facade. This enables relying on light asserts from low-level headers
 # like polyfill or span that might trigger circular includes due to the
 # backend.
@@ -58,7 +53,6 @@
   public_configs = [ ":default_config" ]
   public = [
     "public/pw_assert/assert.h",
-    "public/pw_assert/light.h",
 
     # Needed for PW_ASSERT_ENABLE_DEBUG. Note that depending on :pw_assert to
     # get options.h won't work here since it will trigger the circular include
diff --git a/pw_assert/public/pw_assert/assert.h b/pw_assert/public/pw_assert/assert.h
index a6756a6..95457a8 100644
--- a/pw_assert/public/pw_assert/assert.h
+++ b/pw_assert/public/pw_assert/assert.h
@@ -16,10 +16,6 @@
 #include "pw_assert/options.h"  // For PW_ASSERT_ENABLE_DEBUG
 #include "pw_preprocessor/util.h"
 
-// For backwards compatibility, include check.h from assert.h.
-// TODO(pwbug/350): Remove this include when projects have migrated.
-#include "pw_assert/check.h"
-
 PW_EXTERN_C_START
 
 void pw_assert_HandleFailure(void);
diff --git a/pw_assert/public/pw_assert/light.h b/pw_assert/public/pw_assert/light.h
deleted file mode 100644
index 635bb3f..0000000
--- a/pw_assert/public/pw_assert/light.h
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2021 The Pigweed Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License"); you may not
-// use this file except in compliance with the License. You may obtain a copy of
-// the License at
-//
-//     https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-// License for the specific language governing permissions and limitations under
-// the License.
-#pragma once
-
-// TODO(pwbug/350): Remove the deprecated light.h header in favor of assert.h.
-#include "pw_assert/assert.h"
diff --git a/pw_i2c/register_device.cc b/pw_i2c/register_device.cc
index af8183a..cae58ce 100644
--- a/pw_i2c/register_device.cc
+++ b/pw_i2c/register_device.cc
@@ -14,6 +14,7 @@
 
 #include "pw_i2c/register_device.h"
 
+#include "pw_assert/check.h"
 #include "pw_bytes/byte_builder.h"
 
 namespace pw {
diff --git a/pw_persistent_ram/BUILD.gn b/pw_persistent_ram/BUILD.gn
index f992280..7df09ca 100644
--- a/pw_persistent_ram/BUILD.gn
+++ b/pw_persistent_ram/BUILD.gn
@@ -35,6 +35,7 @@
     dir_pw_assert,
     dir_pw_bytes,
     dir_pw_checksum,
+    dir_pw_preprocessor,
     dir_pw_stream,
   ]
 }
diff --git a/pw_persistent_ram/public/pw_persistent_ram/persistent.h b/pw_persistent_ram/public/pw_persistent_ram/persistent.h
index 8268666..2e53edf 100644
--- a/pw_persistent_ram/public/pw_persistent_ram/persistent.h
+++ b/pw_persistent_ram/public/pw_persistent_ram/persistent.h
@@ -21,6 +21,7 @@
 
 #include "pw_assert/assert.h"
 #include "pw_checksum/crc16_ccitt.h"
+#include "pw_preprocessor/compiler.h"
 
 namespace pw::persistent_ram {
 
diff --git a/pw_result/BUILD.gn b/pw_result/BUILD.gn
index dc4f2e7..7192cbf 100644
--- a/pw_result/BUILD.gn
+++ b/pw_result/BUILD.gn
@@ -27,6 +27,7 @@
   public_configs = [ ":default_config" ]
   public_deps = [
     "$dir_pw_assert",
+    "$dir_pw_preprocessor",
     "$dir_pw_status",
   ]
   public = [ "public/pw_result/result.h" ]
diff --git a/pw_result/public/pw_result/result.h b/pw_result/public/pw_result/result.h
index c0c0ca4..0fcffd1 100644
--- a/pw_result/public/pw_result/result.h
+++ b/pw_result/public/pw_result/result.h
@@ -17,6 +17,7 @@
 #include <utility>
 
 #include "pw_assert/assert.h"
+#include "pw_preprocessor/compiler.h"
 #include "pw_status/status.h"
 
 namespace pw {