Kokoro: Switch from RelWithDebInfo to Release

To try and speed up the presubmits a bit.
Also add some stage duration timings, so we can tell what takes all the
time.

Bug: tint:652
Change-Id: Ic0a25a9485dc58e6d45b5129756fe9e704380d02
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/45341
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
diff --git a/kokoro/linux/cmake-clang-release-asan/build.sh b/kokoro/linux/cmake-clang-release-asan/build.sh
index 5799514..ed598ae 100755
--- a/kokoro/linux/cmake-clang-release-asan/build.sh
+++ b/kokoro/linux/cmake-clang-release-asan/build.sh
@@ -20,7 +20,7 @@
 
 export BUILD_SYSTEM=cmake
 export BUILD_TOOLCHAIN=clang
-export BUILD_TYPE=RelWithDebInfo
+export BUILD_TYPE=Release
 export BUILD_SANITIZER=asan
 
 ${SCRIPT_DIR}/../build.sh
diff --git a/kokoro/linux/cmake-clang-release/build.sh b/kokoro/linux/cmake-clang-release/build.sh
index b889c81..394f5bb 100755
--- a/kokoro/linux/cmake-clang-release/build.sh
+++ b/kokoro/linux/cmake-clang-release/build.sh
@@ -20,6 +20,6 @@
 
 export BUILD_SYSTEM=cmake
 export BUILD_TOOLCHAIN=clang
-export BUILD_TYPE=RelWithDebInfo
+export BUILD_TYPE=Release
 
 ${SCRIPT_DIR}/../build.sh
diff --git a/kokoro/linux/cmake-gcc-release/build.sh b/kokoro/linux/cmake-gcc-release/build.sh
index 1bdee7c..83af742 100755
--- a/kokoro/linux/cmake-gcc-release/build.sh
+++ b/kokoro/linux/cmake-gcc-release/build.sh
@@ -20,6 +20,6 @@
 
 export BUILD_SYSTEM=cmake
 export BUILD_TOOLCHAIN=gcc
-export BUILD_TYPE=RelWithDebInfo
+export BUILD_TYPE=Release
 
 ${SCRIPT_DIR}/../build.sh
diff --git a/kokoro/linux/docker.sh b/kokoro/linux/docker.sh
index d02b6e3..8870b0c 100755
--- a/kokoro/linux/docker.sh
+++ b/kokoro/linux/docker.sh
@@ -18,12 +18,25 @@
 
 function show_cmds { set -x; }
 function hide_cmds { { set +x; } 2>/dev/null; }
+function task_begin {
+    TASK_NAME="$@"
+    SECONDS=0
+}
+function print_last_task_duration {
+    if [ ! -z "${TASK_NAME}" ]; then
+        echo "${TASK_NAME} completed in $(($SECONDS / 3600))h$((($SECONDS / 60) % 60))m$(($SECONDS % 60))s"
+    fi
+}
 function status {
     echo ""
+    echo ""
+    print_last_task_duration
+    echo ""
     echo "*****************************************************************"
     echo "* $@"
     echo "*****************************************************************"
     echo ""
+    task_begin $@
 }
 
 . /bin/using.sh # Declare the bash `using` function for configuring toolchains.