Sandbox soong_build by changing to root directory

This relands I12a0f907753fefd1997ab8b4ea2ac331234093cf along with
a fix to blueprint for absolute paths.

Store the current working directory and then change to the root
directory so that all file accesses must go through helpers in
the android package that properly track dependencies.

Change-Id: I24ac485677aa102eec1a2521d16820da6ee1ae77
Fixes: 146437378
Test: m checkbuild
Test: m OUT_DIR=/tmp/out nothing

2 files changed, 8 insertions, 3 deletions

diff --git a/androidmk/Android.bp b/androidmk/Android.bp
index 41100738c..70fc1f75c 100644
--- a/androidmk/Android.bp
+++ b/androidmk/Android.bp
@@ -41,7 +41,6 @@ bootstrap_go_package {
         "androidmk-parser",
         "blueprint-parser",
         "bpfix-lib",
-        "soong-android",
     ],
 }
 
diff --git a/androidmk/androidmk/android.go b/androidmk/androidmk/android.go
index 0082d8b0b..88609849d 100644
--- a/androidmk/androidmk/android.go
+++ b/androidmk/androidmk/android.go
@@ -15,9 +15,9 @@
 package androidmk
 
 import (
-	"android/soong/android"
 	mkparser "android/soong/androidmk/parser"
 	"fmt"
+	"sort"
 	"strings"
 
 	bpparser "github.com/google/blueprint/parser"
@@ -350,7 +350,13 @@ func splitAndAssign(ctx variableAssignmentContext, splitFunc listSplitFunc, name
 		return err
 	}
 
-	for _, nameClassification := range android.SortedStringKeys(namesByClassification) {
+	var classifications []string
+	for classification := range namesByClassification {
+		classifications = append(classifications, classification)
+	}
+	sort.Strings(classifications)
+
+	for _, nameClassification := range classifications {
 		name := namesByClassification[nameClassification]
 		if component, ok := lists[nameClassification]; ok && !emptyList(component) {
 			err = setVariable(ctx.file, ctx.append, ctx.prefix, name, component, true)