Add //external/arm-optimized-routines to bp2build-incremental.

Test: TH presubmits
Change-Id: I35a182b800b06687b9ba4c1f8daf433c55ada9e2
diff --git a/ci/bp2build.sh b/ci/bp2build.sh
index c52374f..d203967 100755
--- a/ci/bp2build.sh
+++ b/ci/bp2build.sh
@@ -16,11 +16,33 @@
 # output should not be parsed as such.
 rm -f out/ninja_build
 
-# Build targets under bionic/ for various architectures
-tools/bazel --max_idle_secs=5 build --config=bp2build --color=no --curses=no --show_progress_rate_limit=5 --platforms //build/bazel/platforms:android_x86 -k //bionic/... //system/...
-tools/bazel --max_idle_secs=5 build --config=bp2build --color=no --curses=no --show_progress_rate_limit=5 --platforms //build/bazel/platforms:android_x86_64 -k //bionic/... //system/...
-tools/bazel --max_idle_secs=5 build --config=bp2build --color=no --curses=no --show_progress_rate_limit=5 --platforms //build/bazel/platforms:android_arm -k //bionic/... //system/...
-tools/bazel --max_idle_secs=5 build --config=bp2build --color=no --curses=no --show_progress_rate_limit=5 --platforms //build/bazel/platforms:android_arm64 -k //bionic/... //system/...
+# We could create .bazelrc files and use them on buildbots with --bazelrc, but
+# it's simpler to use a list for now.
+BUILD_FLAGS_LIST=(
+  --color=no
+  --curses=no
+  --show_progress_rate_limit=5
+  --config=bp2build
+)
+BUILD_FLAGS="${BUILD_FLAGS_LIST[@]}"
+
+TEST_FLAGS_LIST=(
+  --keep_going
+  --test_output=errors
+)
+TEST_FLAGS="${TEST_FLAGS_LIST[@]}"
+
+# Build targets for various architectures.
+BUILD_TARGETS_LIST=(
+  //bionic/...
+  //system/...
+  //external/arm-optimized-routines/...
+)
+BUILD_TARGETS="${BUILD_TARGETS_LIST[@]}"
+tools/bazel --max_idle_secs=5 build ${BUILD_FLAGS} --platforms //build/bazel/platforms:android_x86 -k ${BUILD_TARGETS}
+tools/bazel --max_idle_secs=5 build ${BUILD_FLAGS} --platforms //build/bazel/platforms:android_x86_64 -k ${BUILD_TARGETS}
+tools/bazel --max_idle_secs=5 build ${BUILD_FLAGS} --platforms //build/bazel/platforms:android_arm -k ${BUILD_TARGETS}
+tools/bazel --max_idle_secs=5 build ${BUILD_FLAGS} --platforms //build/bazel/platforms:android_arm64 -k ${BUILD_TARGETS}
 
 # Run tests.
-tools/bazel --max_idle_secs=5 test --config=bp2build --color=no --curses=no --show_progress_rate_limit=5 --test_output=errors -k //build/bazel/tests/...
+tools/bazel --max_idle_secs=5 test ${BUILD_FLAGS} ${TEST_FLAGS} //build/bazel/tests/...