Add SrcPath to InstallHookContext

Needed by ART to find the intermediate files so that it
can also install them in testcases directory for tests.

Change-Id: If1b2ad132632c5dc7c6c7573b56680e2f422594a
diff --git a/android/hooks.go b/android/hooks.go
index f43a007..85fc081 100644
--- a/android/hooks.go
+++ b/android/hooks.go
@@ -120,6 +120,7 @@
 
 type InstallHookContext interface {
 	ModuleContext
+	SrcPath() Path
 	Path() InstallPath
 	Symlink() bool
 }
@@ -134,10 +135,17 @@
 
 type installHookContext struct {
 	ModuleContext
+	srcPath Path
 	path    InstallPath
 	symlink bool
 }
 
+var _ InstallHookContext = &installHookContext{}
+
+func (x *installHookContext) SrcPath() Path {
+	return x.srcPath
+}
+
 func (x *installHookContext) Path() InstallPath {
 	return x.path
 }
@@ -146,10 +154,11 @@
 	return x.symlink
 }
 
-func (x *hooks) runInstallHooks(ctx ModuleContext, path InstallPath, symlink bool) {
+func (x *hooks) runInstallHooks(ctx ModuleContext, srcPath Path, path InstallPath, symlink bool) {
 	if len(x.install) > 0 {
 		mctx := &installHookContext{
 			ModuleContext: ctx,
+			srcPath:       srcPath,
 			path:          path,
 			symlink:       symlink,
 		}