Remove empty DepsMutator methods

Add an empty DepsMutator to ModuleBase so it doesn't have to be
implemented on every module that doesn't need it.

Test: all soong tests
Change-Id: I545a832a0dbf27386d3080377a75ea482cd9ce59
diff --git a/android/module.go b/android/module.go
index 551824d..f2f1af1 100644
--- a/android/module.go
+++ b/android/module.go
@@ -481,6 +481,8 @@
 	prefer32 func(ctx BaseModuleContext, base *ModuleBase, class OsClass) bool
 }
 
+func (a *ModuleBase) DepsMutator(BottomUpMutatorContext) {}
+
 func (a *ModuleBase) AddProperties(props ...interface{}) {
 	a.registerProps = append(a.registerProps, props...)
 }
diff --git a/android/namespace.go b/android/namespace.go
index b027ceb..dca2b8c 100644
--- a/android/namespace.go
+++ b/android/namespace.go
@@ -366,9 +366,6 @@
 	}
 }
 
-func (n *NamespaceModule) DepsMutator(context BottomUpMutatorContext) {
-}
-
 func (n *NamespaceModule) GenerateAndroidBuildActions(ctx ModuleContext) {
 }
 
diff --git a/android/neverallow_test.go b/android/neverallow_test.go
index 9e4886c..8d53087 100644
--- a/android/neverallow_test.go
+++ b/android/neverallow_test.go
@@ -222,9 +222,6 @@
 	return m
 }
 
-func (p *mockCcLibraryModule) DepsMutator(ctx BottomUpMutatorContext) {
-}
-
 func (p *mockCcLibraryModule) GenerateAndroidBuildActions(ModuleContext) {
 }
 
@@ -244,8 +241,5 @@
 	return m
 }
 
-func (p *mockJavaLibraryModule) DepsMutator(ctx BottomUpMutatorContext) {
-}
-
 func (p *mockJavaLibraryModule) GenerateAndroidBuildActions(ModuleContext) {
 }
diff --git a/android/prebuilt_test.go b/android/prebuilt_test.go
index cd1ffae..b30ca1a 100644
--- a/android/prebuilt_test.go
+++ b/android/prebuilt_test.go
@@ -212,9 +212,6 @@
 	return p.prebuilt.Name(p.ModuleBase.Name())
 }
 
-func (p *prebuiltModule) DepsMutator(ctx BottomUpMutatorContext) {
-}
-
 func (p *prebuiltModule) GenerateAndroidBuildActions(ModuleContext) {
 }
 
diff --git a/apex/key.go b/apex/key.go
index 7e98d2b..6d1032d 100644
--- a/apex/key.go
+++ b/apex/key.go
@@ -19,6 +19,7 @@
 	"io"
 
 	"android/soong/android"
+
 	"github.com/google/blueprint/proptools"
 )
 
@@ -61,9 +62,6 @@
 	return m.properties.Installable == nil || proptools.Bool(m.properties.Installable)
 }
 
-func (m *apexKey) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func (m *apexKey) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	if ctx.Config().FlattenApex() && !ctx.Config().UnbundledBuild() {
 		// Flattened APEXes are not signed
diff --git a/cc/cc.go b/cc/cc.go
index 4c26e60..5a2f0ae 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -1869,9 +1869,6 @@
 func (*Defaults) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 }
 
-func (d *Defaults) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func defaultsFactory() android.Module {
 	return DefaultsFactory()
 }
diff --git a/cc/ndk_headers.go b/cc/ndk_headers.go
index 504a6a0..c0ce9c3 100644
--- a/cc/ndk_headers.go
+++ b/cc/ndk_headers.go
@@ -93,9 +93,6 @@
 	licensePath  android.ModuleSrcPath
 }
 
-func (m *headerModule) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func getHeaderInstallDir(ctx android.ModuleContext, header android.Path, from string,
 	to string) android.OutputPath {
 	// Output path is the sysroot base + "usr/include" + to directory + directory component
@@ -210,9 +207,6 @@
 	licensePath  android.ModuleSrcPath
 }
 
-func (m *versionedHeaderModule) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func (m *versionedHeaderModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	if String(m.properties.License) == "" {
 		ctx.PropertyErrorf("license", "field is required")
@@ -335,9 +329,6 @@
 	licensePath  android.ModuleSrcPath
 }
 
-func (m *preprocessedHeadersModule) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func (m *preprocessedHeadersModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	if String(m.properties.License) == "" {
 		ctx.PropertyErrorf("license", "field is required")
diff --git a/genrule/genrule.go b/genrule/genrule.go
index 77bc196..7695ffb 100644
--- a/genrule/genrule.go
+++ b/genrule/genrule.go
@@ -528,9 +528,6 @@
 func (*Defaults) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 }
 
-func (d *Defaults) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func defaultsFactory() android.Module {
 	return DefaultsFactory()
 }
diff --git a/genrule/genrule_test.go b/genrule/genrule_test.go
index 70b9090..19b22f7 100644
--- a/genrule/genrule_test.go
+++ b/genrule/genrule_test.go
@@ -519,8 +519,6 @@
 	return module
 }
 
-func (t *testTool) DepsMutator(ctx android.BottomUpMutatorContext) {}
-
 func (t *testTool) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	t.outputFile = android.PathForTesting("out", ctx.ModuleName())
 }
diff --git a/java/app.go b/java/app.go
index cc863e6..e9c12e0 100644
--- a/java/app.go
+++ b/java/app.go
@@ -503,9 +503,6 @@
 	return module
 }
 
-func (c *AndroidAppCertificate) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func (c *AndroidAppCertificate) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	cert := String(c.properties.Certificate)
 	c.Certificate = Certificate{
diff --git a/java/droiddoc.go b/java/droiddoc.go
index 01e2989..d893c09 100644
--- a/java/droiddoc.go
+++ b/java/droiddoc.go
@@ -1816,9 +1816,6 @@
 func (*DocDefaults) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 }
 
-func (d *DocDefaults) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func DocDefaultsFactory() android.Module {
 	module := &DocDefaults{}
 
diff --git a/java/java.go b/java/java.go
index 230e8f2..70c6c43 100644
--- a/java/java.go
+++ b/java/java.go
@@ -1840,9 +1840,6 @@
 func (*Defaults) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 }
 
-func (d *Defaults) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func defaultsFactory() android.Module {
 	return DefaultsFactory()
 }
diff --git a/java/prebuilt_apis.go b/java/prebuilt_apis.go
index c11e010..0410daf 100644
--- a/java/prebuilt_apis.go
+++ b/java/prebuilt_apis.go
@@ -47,10 +47,6 @@
 	properties prebuiltApisProperties
 }
 
-func (module *prebuiltApis) DepsMutator(ctx android.BottomUpMutatorContext) {
-	// no need to implement
-}
-
 func (module *prebuiltApis) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	// no need to implement
 }
diff --git a/phony/phony.go b/phony/phony.go
index 0c62e8a..e8a6550 100644
--- a/phony/phony.go
+++ b/phony/phony.go
@@ -38,9 +38,6 @@
 	return module
 }
 
-func (p *phony) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func (p *phony) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	p.requiredModuleNames = ctx.RequiredModuleNames()
 	if len(p.requiredModuleNames) == 0 {
diff --git a/python/defaults.go b/python/defaults.go
index 641aca4..dba23a7 100644
--- a/python/defaults.go
+++ b/python/defaults.go
@@ -30,9 +30,6 @@
 func (d *Defaults) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 }
 
-func (d *Defaults) DepsMutator(ctx android.BottomUpMutatorContext) {
-}
-
 func defaultsFactory() android.Module {
 	return DefaultsFactory()
 }