Implement sysprop_library API stability check

sysprop_library now checks the API stability itself, cutting dependency
on java_sdk_library. Under the directory {module_dir}/api,
{module_name}-current.txt and {module_name}-latest.txt hold API
signatures.

When sysprop_library is built, or a user run "m {module_name}-check-api"
command, API check is performed. First, current.txt must have exactly
same signature with built sysprop_library module. Second, current.txt
must be compatible with latest.txt.

Build system emits a handy error message to generate/update those API
files, in case of missing or mismatching. Also, a script file for
freezing API files is introduced.

Bug: 131637873
Test: 1) m && boot blueline
Test: 2) m {sysprop_library} performs API check
Test: 3) manual test for check-api, freezing api
Change-Id: I9d25f5dc64299e666527ca8e23d7233966901c4e

cc/sysprop.go

@@ -21,6 +21,7 @@ import (
 )
 
 type syspropLibraryInterface interface {
+	BaseModuleName() string
 	CcModuleName() string
 }
 
@@ -42,6 +43,6 @@ func SyspropMutator(mctx android.BottomUpMutatorContext) {
 		syspropImplLibrariesLock.Lock()
 		defer syspropImplLibrariesLock.Unlock()
 
-		syspropImplLibraries[mctx.ModuleName()] = m.CcModuleName()
+		syspropImplLibraries[m.BaseModuleName()] = m.CcModuleName()
 	}
 }