golang: Roll to version 1.15.7

BUG=b/189265774
TEST=presubmit
RELEASE_NOTE=Update dev-lang/go to 1.15.7

Disallow-Recycled-Builds: dedede-cq, zork-cq
Change-Id: I7bb67f88bcd1a45c7598b40f39f63cda31891493
Reviewed-on: https://cos-review.googlesource.com/c/third_party/overlays/chromiumos-overlay/+/17050
Reviewed-by: Roy Yang <royyang@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
diff --git a/dev-lang/go/Manifest b/dev-lang/go/Manifest
index 143dddf..b337c77 100644
--- a/dev-lang/go/Manifest
+++ b/dev-lang/go/Manifest
@@ -1,2 +1,2 @@
-DIST go1.13.5.src.tar.gz 21629437 BLAKE2B c39a52e73136a322a1b6b4ee6888672848ff2b3278d8034ec25b93101fff2b63212d66c065d3d974ca7e8686cba8a9ea9c4fedb23cad51b6cd76adae6db6eb42 SHA512 bc9ddb12855c66dba5fe859bd13b7b3163259b8a8b0d3cbf6892e528ae4c6418c6b4c0d49838e7a5fc2e9f404484899b8f30c45e49e7d30109093025b62ed6c0
+DIST go1.15.7.src.tar.gz 23764672 BLAKE2B 664822be79c5190a9756afc8d8f4fcc02512cffa215d2ad12d5037faf4103563634b9b0b62a2ccd9cbe0f1c0669af5ca7ee335544514fa7452ce954a47917080 SHA512 504e3e79b67a4269119ba157173970b4bb228cba20b66d16cb64def83df691544dcf67c9c1b78e3376512340c378a5e61535cbc9803c4266882667400d477b64
 DIST go1.4-bootstrap-20170531.tar.gz 11315348 BLAKE2B bdc66bc1aca3f86ca8deaa01f598db955d6de6dd069bc2ae095a4335a9b113079aff93a23310c3bb6ea7e91b0ce0ef45394ce7094d234f7daffc088af4c1b6e0 SHA512 f04b4822aae0953ec2982ab9e8ad02dde588bbf3cf27ad294178f7faa7c3359ee20e77c2c06b293e88d9b680b79c4b5958f1f772f0710637324a3b8c024c1bc3
diff --git a/dev-lang/go/go-1.13.5-r1.ebuild b/dev-lang/go/go-1.13.5-r1.ebuild
deleted file mode 120000
index e21c17f..0000000
--- a/dev-lang/go/go-1.13.5-r1.ebuild
+++ /dev/null
@@ -1 +0,0 @@
-go-1.13.5.ebuild
\ No newline at end of file
diff --git a/dev-lang/go/go-1.15.7-r1.ebuild b/dev-lang/go/go-1.15.7-r1.ebuild
new file mode 120000
index 0000000..e6acafb
--- /dev/null
+++ b/dev-lang/go/go-1.15.7-r1.ebuild
@@ -0,0 +1 @@
+go-1.15.7.ebuild
\ No newline at end of file
diff --git a/dev-lang/go/go-1.13.5.ebuild b/dev-lang/go/go-1.15.7.ebuild
similarity index 100%
rename from dev-lang/go/go-1.13.5.ebuild
rename to dev-lang/go/go-1.15.7.ebuild