Consolidate baseContext, BaseContext, and BaseModuleContext

blueprint.BaseModuleContext is the set of methods available to all
module-specific calls (GenerateBuildActions or mutators).  The
android package split the same functionality across baseContext (nee
androidBaseContext), BaseModuleContext, and BaseContext.
Consolidate all of them into android.BaseModuleContext.

Test: m checkbuild
Change-Id: I2d7f5c56fd4424032cb93edff6dc730ff33e4f1e
diff --git a/android/api_levels.go b/android/api_levels.go
index 51d4703..961685a 100644
--- a/android/api_levels.go
+++ b/android/api_levels.go
@@ -85,7 +85,7 @@
 // * Numeric API levels are simply converted.
 // * "minimum" and "current" are not currently handled since the former is
 //   NDK specific and the latter has inconsistent meaning.
-func ApiStrToNum(ctx BaseContext, apiLevel string) (int, error) {
+func ApiStrToNum(ctx BaseModuleContext, apiLevel string) (int, error) {
 	num, ok := getApiLevelsMap(ctx.Config())[apiLevel]
 	if ok {
 		return num, nil