[beta] Prepare the 1.27.0 beta release

This commit prepares the 1.27.0 beta release by doing:

* Update the release channel to `beta`
* Update Cargo's submodule
* Update `stdsimd`'s submodule
* Update the bootstrap compiler to the freshly minted 1.26.0 stable release
* Don't attempt to verify clippy/miri build

Author: alexcrichton

src/Cargo.lock

@@ -556,15 +556,6 @@ tool_extended!((self, builder),
     };
     Miri, miri, "src/tools/miri", "miri", {};
     Rls, rls, "src/tools/rls", "rls", {
-        let clippy = builder.ensure(Clippy {
-            compiler: self.compiler,
-            target: self.target,
-            extra_features: Vec::new(),
-        });
-        let channel = &builder.config.channel;
-        if clippy.is_some() && channel != "stable" && channel != "beta" {
-            self.extra_features.push("clippy".to_owned());
-        }
         builder.ensure(native::Openssl {
             target: self.target,
         });

src/bootstrap/tool.rs

@@ -30,9 +30,7 @@ python2.7 "$X_PY" test --no-fail-fast \
     src/doc/reference \
     src/doc/rust-by-example \
     src/tools/rls \
-    src/tools/rustfmt \
-    src/tools/miri \
-    src/tools/clippy
+    src/tools/rustfmt
 set -e
 
 cat "$TOOLSTATE_FILE"
@@ -66,8 +64,6 @@ verify_status reference src/doc/reference
 verify_status rust-by-example src/doc/rust-by-example
 verify_status rls src/tool/rls
 verify_status rustfmt src/tool/rustfmt
-verify_status clippy-driver src/tool/clippy
-verify_status miri src/tool/miri
 
 if [ "$RUST_RELEASE_CHANNEL" = nightly -a -n "${TOOLSTATE_REPO_ACCESS_TOKEN+is_set}" ]; then
     . "$(dirname $0)/repo.sh"

src/ci/docker/x86_64-gnu-tools/checktools.sh

@@ -48,7 +48,7 @@ fi
 #
 # FIXME: need a scheme for changing this `nightly` value to `beta` and `stable`
 #        either automatically or manually.
-export RUST_RELEASE_CHANNEL=nightly
+export RUST_RELEASE_CHANNEL=beta
 if [ "$DEPLOY$DEPLOY_ALT" != "" ]; then
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --release-channel=$RUST_RELEASE_CHANNEL"
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-static-stdcpp"

src/ci/run.sh

@@ -12,9 +12,9 @@
 # source tarball for a stable release you'll likely see `1.x.0` for rustc and
 # `0.x.0` for Cargo where they were released on `date`.
 
-date: 2018-04-24
-rustc: beta
-cargo: beta
+date: 2018-05-07
+rustc: 1.26.0
+cargo: 0.27.0
 
 # When making a stable release the process currently looks like:
 #
@@ -34,4 +34,4 @@ cargo: beta
 # looking at a beta source tarball and it's uncommented we'll shortly comment it
 # out.
 
-#dev: 1
+dev: 1