Remove GCC checks

Clang is always used now, so we can remove all the GCC checks. Removing
GCC-specific configuration will happen in the next CL.

Test: m
Change-Id: I4835ecf6062159315d0dfb07b098e60bff033a8a
diff --git a/cc/cc.go b/cc/cc.go
index 640c552..5f3baea 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -136,7 +136,6 @@
 	SystemIncludeFlags []string
 
 	Toolchain config.Toolchain
-	Clang     bool
 	Tidy      bool
 	Coverage  bool
 	SAbiDump  bool
@@ -165,9 +164,6 @@
 	// Deprecated. true is the default, false is invalid.
 	Clang *bool `android:"arch_variant"`
 
-	// Some internals still need GCC (toolchain_library)
-	Gcc bool `blueprint:"mutated"`
-
 	// Minimum sdk version supported when compiling against the ndk
 	Sdk_version *string
 
@@ -220,7 +216,6 @@
 type ModuleContextIntf interface {
 	static() bool
 	staticBinary() bool
-	clang() bool
 	toolchain() config.Toolchain
 	useSdk() bool
 	sdkVersion() string
@@ -513,10 +508,6 @@
 	ctx BaseModuleContext
 }
 
-func (ctx *moduleContextImpl) clang() bool {
-	return ctx.mod.clang(ctx.ctx)
-}
-
 func (ctx *moduleContextImpl) toolchain() config.Toolchain {
 	return ctx.mod.toolchain(ctx.ctx)
 }
@@ -733,9 +724,12 @@
 		return
 	}
 
+	if c.Properties.Clang != nil && *c.Properties.Clang == false {
+		ctx.PropertyErrorf("clang", "false (GCC) is no longer supported")
+	}
+
 	flags := Flags{
 		Toolchain: c.toolchain(ctx),
-		Clang:     c.clang(ctx),
 	}
 	if c.compiler != nil {
 		flags = c.compiler.compilerFlags(ctx, flags, deps)
@@ -1099,14 +1093,6 @@
 	}
 }
 
-func (c *Module) clang(ctx BaseModuleContext) bool {
-	if c.Properties.Clang != nil && *c.Properties.Clang == false {
-		ctx.PropertyErrorf("clang", "false (GCC) is no longer supported")
-	}
-
-	return !c.Properties.Gcc
-}
-
 // Whether a module can link to another module, taking into
 // account NDK linking.
 func checkLinkType(ctx android.ModuleContext, from *Module, to *Module, tag dependencyTag) {