Roll src/third_party/boringssl/src 0e4a448ab..2507d9e70

https://boringssl.googlesource.com/boringssl/+log/0e4a448ab8aa66a38593f68d19fa0a2e340833e4..2507d9e7090fcd461f33f3b89bcd56c9a7476a04

BUG=none

Change-Id: I34232babbf1adfdb663142b1f6970ed490b16399
Reviewed-on: https://chromium-review.googlesource.com/586645Reviewed-by: Adam Langley <agl@chromium.org>
Commit-Queue: David Benjamin <davidben@chromium.org>
Cr-Commit-Position: refs/heads/master@{#490632}

DEPS

@@ -72,7 +72,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling BoringSSL
   # and whatever else without interference from each other.
-  'boringssl_revision': '0e4a448ab8aa66a38593f68d19fa0a2e340833e4',
+  'boringssl_revision': '2507d9e7090fcd461f33f3b89bcd56c9a7476a04',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling google-toolbox-for-mac
   # and whatever else without interference from each other.

third_party/boringssl/BUILD.generated.gni

@@ -319,6 +319,7 @@ crypto_sources = [
   "src/include/openssl/rsa.h",
   "src/include/openssl/safestack.h",
   "src/include/openssl/sha.h",
+  "src/include/openssl/span.h",
   "src/include/openssl/srtp.h",
   "src/include/openssl/stack.h",
   "src/include/openssl/thread.h",
@@ -352,8 +353,8 @@ ssl_sources = [
   "src/ssl/ssl_buffer.cc",
   "src/ssl/ssl_cert.cc",
   "src/ssl/ssl_cipher.cc",
-  "src/ssl/ssl_ecdh.cc",
   "src/ssl/ssl_file.cc",
+  "src/ssl/ssl_key_share.cc",
   "src/ssl/ssl_lib.cc",
   "src/ssl/ssl_privkey.cc",
   "src/ssl/ssl_session.cc",

third_party/boringssl/BUILD.generated_tests.gni

@@ -69,5 +69,6 @@ crypto_test_sources = [
 
 ssl_test_sources = [
   "src/crypto/test/gtest_main.cc",
+  "src/ssl/span_test.cc",
   "src/ssl/ssl_test.cc",
 ]

third_party/boringssl/BUILD.gn

@@ -22,6 +22,7 @@ config("external_config") {
 config("internal_config") {
   visibility = [ ":*" ]  # Only targets in this file can depend on this.
   defines = [
+    "BORINGSSL_ALLOW_CXX_RUNTIME",
     "BORINGSSL_IMPLEMENTATION",
     "BORINGSSL_NO_STATIC_INITIALIZER",
     "OPENSSL_SMALL",