RNTester Android: always compile Fabric files

Summary:
This commit makes both `:ReactAndroid` and `:rn-tester:android:app` always compile in Fabric codegen outputs. However, one may still enable/disable Fabric at runtime by setting `USE_FABRIC` env var (set to 1 or 0, default is 0).

Note that we can't register custom components specific to the app, yet, so only the components in react-native github repo is covered by this commit.

RNTester doesn't enable Fabric by default yet due to known UI bugs that haven't been addressed yet.

Changelog: [Internal]

Reviewed By: mdvacca

Differential Revision: D25674311

fbshipit-source-id: 8db660c959319250ebc683c84076677cf6489e94

ReactAndroid/build.gradle

@@ -33,11 +33,6 @@ def thirdPartyNdkDir = new File("$buildDir/third-party-ndk")
 //   - glog-0.3.5
 def dependenciesPath = System.getenv("REACT_NATIVE_DEPENDENCIES")
 
-// The 'USE_FABRIC' environment variable will build Fabric C++ code into the bundle
-// USE_FABRIC=0 will build RN excluding fabric
-// USE_FABRIC=1 will build RN including fabric
-def enableFabric = (System.getenv('USE_FABRIC') ?: '0').toBoolean()
-
 // The Boost library is a very large download (>100MB).
 // If Boost is already present on your system, define the REACT_NATIVE_BOOST_PATH env variable
 // and the build will use that.
@@ -318,7 +313,6 @@ def buildReactNdkLib = tasks.register("buildReactNdkLib", Exec) {
             "REACT_COMMON_DIR=$projectDir/../ReactCommon",
             "REACT_GENERATED_SRC_DIR=$buildDir/generated/source",
             "REACT_SRC_DIR=$projectDir/src/main/java/com/facebook/react",
-            "BUILD_FABRIC=$enableFabric",
             "-C", file("src/main/jni/react/jni").absolutePath,
             "--jobs", project.findProperty("jobs") ?: Runtime.runtime.availableProcessors()
     )

ReactAndroid/src/main/jni/react/jni/Android.mk

@@ -134,10 +134,7 @@ include $(REACT_SRC_DIR)/reactperflogger/jni/Android.mk
 # TODO (T48588859): Restructure this target to align with dir structure: "react/nativemodule/..."
 # Note: Update this only when ready to minimize breaking changes.
 include $(REACT_SRC_DIR)/turbomodule/core/jni/Android.mk
-
-ifeq ($(BUILD_FABRIC),true)
-  include $(REACT_SRC_DIR)/fabric/jni/Android.mk
-endif
+include $(REACT_SRC_DIR)/fabric/jni/Android.mk
 
 # TODO(ramanpreet):
 #   Why doesn't this import-module call generate a jscexecutor.so file?

ReactCommon/jsi/Android.mk

@@ -32,8 +32,8 @@ LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)
 LOCAL_CFLAGS := -fexceptions -frtti -O3
 LOCAL_SHARED_LIBRARIES := libfolly_json libjsc glog
 
-ifeq ($(BUILD_FABRIC),true)
-  LOCAL_CFLAGS += -DRN_FABRIC_ENABLED
-endif
+# TODO: Remove this flag when ready.
+# Android has this enabled by default, but the flag is still needed for iOS.
+LOCAL_CFLAGS += -DRN_FABRIC_ENABLED
 
 include $(BUILD_STATIC_LIBRARY)

packages/rn-tester/android/app/build.gradle

@@ -66,7 +66,7 @@ plugins {
  *   // Root dir for all JS files for the app. Defaults to `root` above.
  *   jsRootDir: "../..",
  *
- *   // Enable Fabric at build time and runtime.
+ *   // Enable Fabric at runtime.
  *   enableFabric: true,
  *
  *   // Java package name to use for any codegen artifacts produced during build time.
@@ -113,7 +113,7 @@ def enableProguardInReleaseBuilds = true
 def enableCodegen = project.ext.react.enableCodegen
 
 /**
- * Build and enable Fabric in RN Tester app.
+ * Enable Fabric in RN Tester app.
  */
 def enableFabric = project.ext.react.enableFabric
 

scripts/generate-native-modules-specs-cli.js

@@ -26,9 +26,7 @@ const path = require('path');
 const USE_FABRIC = process.env.USE_FABRIC != null && !!process.env.USE_FABRIC;
 
 const GENERATORS = {
-  android: USE_FABRIC
-    ? ['componentsAndroid', 'modulesAndroid']
-    : ['modulesAndroid'],
+  android: ['componentsAndroid', 'modulesAndroid'],
   ios: ['modulesIOS'],
 };