Upgrade to 3.29

Update V8 to 3.29.88.17 and update makefiles to support building on
all the relevant platforms.

Bug: 17370214

Change-Id: Ia3407c157fd8d72a93e23d8318ccaf6ecf77fa4e
diff --git a/src/libplatform/DEPS b/src/libplatform/DEPS
new file mode 100644
index 0000000..2ea3359
--- /dev/null
+++ b/src/libplatform/DEPS
@@ -0,0 +1,8 @@
+include_rules = [
+  "-include",
+  "+include/libplatform",
+  "+include/v8-platform.h",
+  "-src",
+  "+src/base",
+  "+src/libplatform",
+]