Add optional public header checking to GN build

You can invoke this either using the "--check" argument to the gen command (for use on buildbots) or by running "gn check" (for developer on-demand use).

This adds support for "public" headers for a target, and an optional "--check" flag to the gen command that implements checkdeps-like include checking. Basically if you include a file that's declared in the build, it has to be in the public section of one of your dependents (or that dependent doesn't have a public section, which implies everything is public).

This roughly maps to Blaze's behavior around the public headers.

Moves modp_b64 build file to main tree.

Remove modp_b64 hack for older versions of VC missing stdint (this included basictypes which caused a header check failure).

I also added some base dependencies and some other minor build changes to solve some other issues identified by the check. The remaining one is that a file in base/metrics depends on ipc (!)

BUG=
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/216903004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@262216 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 12 insertions, 17 deletions

diff --git a/third_party/modp_b64/BUILD.gn b/third_party/modp_b64/BUILD.gn
new file mode 100644
index 0000000..539abe1
--- /dev/null
+++ b/third_party/modp_b64/BUILD.gn
@@ -0,0 +1,11 @@
+# Copyright (c) 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+static_library("modp_b64") {
+  sources = [
+    "modp_b64.cc",
+    "modp_b64.h",
+    "modp_b64_data.h",
+  ]
+}
diff --git a/third_party/modp_b64/README.chromium b/third_party/modp_b64/README.chromium
index 26eed1e..35b9e54 100644
--- a/third_party/modp_b64/README.chromium
+++ b/third_party/modp_b64/README.chromium
@@ -11,12 +11,5 @@ and to fix compilation errors that occur under VC8.  The file was renamed
 modp_b64.cc to force it to be compiled as C++ so that the inclusion of
 basictypes.h could be possible.
 
-The file modp_b64_data.h was generated by modp_b64_gen.c (under Linux),
-which is not included in this directory.  The resulting header was
-modified to not include <stdint.h> when COMPILER_MSVC is defined (since
-that header file does not exist under VC8), but instead in that case to
-include "base/basictypes.h" and provide the required typedefs for
-uint8_t and uint32_t using uint8 and uint32.
-
 The modp_b64.cc and modp_b64.h files were modified to make them safe on
-64-bit systems.
\ No newline at end of file
+64-bit systems.
diff --git a/third_party/modp_b64/modp_b64_data.h b/third_party/modp_b64/modp_b64_data.h
index aca6f0f..fb85890 100644
--- a/third_party/modp_b64/modp_b64_data.h
+++ b/third_party/modp_b64/modp_b64_data.h
@@ -1,14 +1,5 @@
 #include "build/build_config.h"
-#if !defined(COMPILER_MSVC)
 #include <stdint.h>
-#else
-// VC8 doesn't have stdint.h.  On the other hand, some compilers don't like
-// the below code, because basictypes.h itself includes stdint.h and the
-// typedefs below can cause conflicts.
-#include "base/basictypes.h"
-typedef uint8 uint8_t;
-typedef uint32 uint32_t;
-#endif
 
 #define CHAR62 '+'
 #define CHAR63 '/'