tree e4f4c4dee164a446bebe98adf7d8936dad7c63e9
parent f4ffafb1a3a2d103105650fcd9720aa390360a12
author Ying Wang <wangying@google.com> 1429045846 -0700
committer Ying Wang <wangying@google.com> 1437438668 -0700

Auto-clean host tools when switching between apps_only and platform build.

For apps_only (also PDK build) we use prebuilt host tools in
prebuilts/sdk/tools; For platform build we use tools built from source.
Auto-clean intermediate files of these tools when build type change is
detected.

Bug: 20213206
Change-Id: I9173af322684c017fdb91a3abfbe39ecfe5650e9
(cherry-pick from commit 036b53b6de3cc2a5de46be31eeb4d07ffb0d057f)