Integrate bazelenv.sh environment variables into soong_ui environment.

This removes the need to source bazelenv.sh for USE_BAZEL_ANALYSIS, and
unifies mixed builds to use the checked in tools/bazel and bazelrc.

It also unifies all bazel-related output to be in out/bazel.

Without aosp/1502095, this change still requires toplevel_output_directories to be an empty
list, otherwise there'll be this error:

ERROR: Directories specified with toplevel_output_directories should be
ignored and can not be used as sources.

Test: With aosp/1441774: rm -rf out/ && lunch aosp_cf_x86_auto && USE_BAZEL_ANALYSIS=1 m libc && prebuilts/build-tools/linux-x86/bin/ninja -f out/combined-aosp_cf_x86_auto.ninja -t commands libc | grep bazel-out | wc -l # 2 results
Change-Id: I69b217ec88da531415792bb6e04b6a194ca4718d
diff --git a/android/bazel_handler.go b/android/bazel_handler.go
index c87a945..5c7d9fc 100644
--- a/android/bazel_handler.go
+++ b/android/bazel_handler.go
@@ -192,8 +192,7 @@
 func (context *bazelContext) issueBazelCommand(command string, labels []string,
 	extraFlags ...string) (string, error) {
 
-	cmdFlags := []string{"--bazelrc=build/bazel/common.bazelrc",
-		"--output_base=" + context.outputBase, command}
+	cmdFlags := []string{"--output_base=" + context.outputBase, command}
 	cmdFlags = append(cmdFlags, labels...)
 	cmdFlags = append(cmdFlags, extraFlags...)
 
diff --git a/bazel/bazelenv.sh b/bazel/bazelenv.sh
deleted file mode 100755
index fcf71f1..0000000
--- a/bazel/bazelenv.sh
+++ /dev/null
@@ -1,78 +0,0 @@
-#!/bin/bash
-
-# Copyright 2020 Google Inc. All rights reserved.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-# Helper script for setting environment variables required for Bazel/Soong
-# mixed builds prototype. For development use only.
-#
-# Usage:
-#   export BAZEL_PATH=[some_bazel_path] && source bazelenv.sh
-#
-# If BAZEL_PATH is not set, `which bazel` will be used
-# to locate the appropriate bazel to use.
-
-
-# Function to find top of the source tree (if $TOP isn't set) by walking up the
-# tree.
-function gettop
-{
-    local TOPFILE=build/soong/root.bp
-    if [ -n "${TOP-}" -a -f "${TOP-}/${TOPFILE}" ] ; then
-        # The following circumlocution ensures we remove symlinks from TOP.
-        (cd $TOP; PWD= /bin/pwd)
-    else
-        if [ -f $TOPFILE ] ; then
-            # The following circumlocution (repeated below as well) ensures
-            # that we record the true directory name and not one that is
-            # faked up with symlink names.
-            PWD= /bin/pwd
-        else
-            local HERE=$PWD
-            T=
-            while [ \( ! \( -f $TOPFILE \) \) -a \( $PWD != "/" \) ]; do
-                \cd ..
-                T=`PWD= /bin/pwd -P`
-            done
-            \cd $HERE
-            if [ -f "$T/$TOPFILE" ]; then
-                echo $T
-            fi
-        fi
-    fi
-}
-
-BASE_DIR="$(mktemp -d)"
-
-if [ -z "$BAZEL_PATH" ] ; then
-    export BAZEL_PATH="$(which bazel)"
-fi
-
-# TODO(cparsons): Use USE_BAZEL=1 instead once "mixed Soong/Bazel builds" are
-# production ready.
-export USE_BAZEL_ANALYSIS=1
-# TODO(cparsons): Retrieve this information in either envsetup.sh or 
-# bazel.sh.
-export BAZEL_HOME="$BASE_DIR/bazelhome"
-export BAZEL_OUTPUT_BASE="$BASE_DIR/output"
-export BAZEL_WORKSPACE="$(gettop)"
-
-echo "USE_BAZEL_ANALYSIS=${USE_BAZEL_ANALYSIS}"
-echo "BAZEL_PATH=${BAZEL_PATH}"
-echo "BAZEL_HOME=${BAZEL_HOME}"
-echo "BAZEL_OUTPUT_BASE=${BAZEL_OUTPUT_BASE}"
-echo "BAZEL_WORKSPACE=${BAZEL_WORKSPACE}"
-
-mkdir -p $BAZEL_HOME
-mkdir -p $BAZEL_OUTPUT_BASE
diff --git a/bazel/master.WORKSPACE.bazel b/bazel/master.WORKSPACE.bazel
deleted file mode 100644
index e69de29..0000000
--- a/bazel/master.WORKSPACE.bazel
+++ /dev/null
diff --git a/ui/build/config.go b/ui/build/config.go
index 641aae6..229bd5c 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -703,6 +703,10 @@
 	return c.ninjaArgs
 }
 
+func (c *configImpl) BazelOutDir() string {
+	return filepath.Join(c.OutDir(), "bazel")
+}
+
 func (c *configImpl) SoongOutDir() string {
 	return filepath.Join(c.OutDir(), "soong")
 }
diff --git a/ui/build/soong.go b/ui/build/soong.go
index b20237c..bb5cbf0 100644
--- a/ui/build/soong.go
+++ b/ui/build/soong.go
@@ -133,6 +133,13 @@
 			"-j", strconv.Itoa(config.Parallel()),
 			"--frontend_file", fifo,
 			"-f", filepath.Join(config.SoongOutDir(), file))
+
+		// For Bazel mixed builds.
+		cmd.Environment.Set("BAZEL_PATH", "./tools/bazel")
+		cmd.Environment.Set("BAZEL_HOME", filepath.Join(config.BazelOutDir(), "bazelhome"))
+		cmd.Environment.Set("BAZEL_OUTPUT_BASE", filepath.Join(config.BazelOutDir(), "output"))
+		cmd.Environment.Set("BAZEL_WORKSPACE", absPath(ctx, "."))
+
 		cmd.Environment.Set("SOONG_SANDBOX_SOONG_BUILD", "true")
 		cmd.Sandbox = soongSandbox
 		cmd.RunAndStreamOrFatal()