Add fee manager mode interface

contracts/upgradeable_contracts/BaseFeeManager.sol

@@ -40,6 +40,8 @@ contract BaseFeeManager is EternalStorage {
         distributeFeeProportionally(_fee, REWARD_FOR_TRANSFERRING_FROM_HOME);
     }
 
+    function getFeeManagerMode() public pure returns(bytes4);
+
     function random(uint256 _count) public view returns(uint256) {
         return uint256(blockhash(block.number.sub(1))) % _count;
     }

contracts/upgradeable_contracts/RewardableBridge.sol

@@ -23,6 +23,20 @@ contract RewardableBridge is Ownable {
         return fee;
     }
 
+    function getFeeManagerMode() public view returns(bytes4) {
+        bytes4 mode;
+        bytes memory callData = abi.encodeWithSignature("getFeeManagerMode()");
+        address feeManager = feeManagerContract();
+        assembly {
+            let result := callcode(gas, feeManager, 0x0, add(callData, 0x20), mload(callData), 0, 4)
+            mode := mload(0)
+
+            switch result
+            case 0 { revert(0, 0) }
+        }
+        return mode;
+    }
+
     function feeManagerContract() public view returns(address) {
         return addressStorage[keccak256(abi.encodePacked("feeManagerContract"))];
     }

contracts/upgradeable_contracts/erc20_to_native/FeeManagerErcToNative.sol

@@ -7,6 +7,10 @@ import "../Sacrifice.sol";
 
 contract FeeManagerErcToNative is BaseFeeManager {
 
+    function getFeeManagerMode() public pure returns(bytes4) {
+        return bytes4(keccak256(abi.encodePacked("manages-both-directions")));
+    }
+
     function blockRewardContract() internal view returns(IBlockReward) {
         return IBlockReward(addressStorage[keccak256(abi.encodePacked("blockRewardContract"))]);
     }

contracts/upgradeable_contracts/native_to_erc20/FeeManagerNativeToErc.sol

@@ -7,6 +7,10 @@ import "../Sacrifice.sol";
 
 contract FeeManagerNativeToErc is BaseFeeManager {
 
+    function getFeeManagerMode() public pure returns(bytes4) {
+        return bytes4(keccak256(abi.encodePacked("manages-one-direction")));
+    }
+
     function erc677token() public view returns(IBurnableMintableERC677Token) {
         return IBurnableMintableERC677Token(addressStorage[keccak256(abi.encodePacked("erc677token"))]);
     }

test/erc_to_native/home_bridge.test.js

@@ -917,6 +917,18 @@ contract('HomeBridge_ERC20_to_Native', async (accounts) => {
       const bridgeFee = await homeBridge.getFee()
       bridgeFee.should.be.bignumber.equal(fee)
     })
+    it('should be able to get fee manager mode', async () => {
+      // Given
+      const feeManager = await FeeManagerErcToNative.new()
+      const bothDirectionsModeHash = '0xd7de965f'
+
+      // When
+      await homeBridge.setFeeManagerContract(feeManager.address, { from: owner }).should.be.fulfilled
+
+      // Then
+      const feeManagerMode = await homeBridge.getFeeManagerMode()
+      feeManagerMode.should.be.equals(bothDirectionsModeHash)
+    })
   })
   describe('#feeManager_ExecuteAffirmation', async () => {
     it('should distribute fee to validator', async () => {

test/native_to_erc/foreign_bridge_test.js

@@ -590,6 +590,19 @@ contract('ForeignBridge', async (accounts) => {
       const bridgeFee = await foreignBridge.getFee()
       bridgeFee.should.be.bignumber.equal(newFee)
     })
+
+    it('should be able to get fee manager mode', async () => {
+      // Given
+      const feeManager = await FeeManagerNativeToErc.new()
+      const oneDirectionsModeHash = '0xf2aed8f7'
+
+      // When
+      await foreignBridge.rewardableInitialize(rewardableValidators.address, token.address, oneEther, halfEther, minPerTx, gasPrice, requireBlockConfirmations, homeDailyLimit, homeMaxPerTx, owner, feeManager.address, fee).should.be.fulfilled;
+
+      // Then
+      const feeManagerMode = await foreignBridge.getFeeManagerMode()
+      feeManagerMode.should.be.equals(oneDirectionsModeHash)
+    })
   })
 
   describe('#RewardableBridge_executeSignatures', async () => {

test/native_to_erc/home_bridge_test.js

@@ -631,6 +631,18 @@ contract('HomeBridge', async (accounts) => {
       const bridgeFee = await homeBridge.getFee()
       bridgeFee.should.be.bignumber.equal(newFee)
     })
+    it('should be able to get fee manager mode', async () => {
+      // Given
+      const feeManager = await FeeManagerNativeToErc.new()
+      const oneDirectionsModeHash = '0xf2aed8f7'
+
+      // When
+      await homeBridge.rewardableInitialize(rewardableValidators.address, oneEther, halfEther, minPerTx, gasPrice, requireBlockConfirmations, foreignDailyLimit, foreignMaxPerTx, owner, feeManager.address, fee).should.be.fulfilled;
+
+      // Then
+      const feeManagerMode = await homeBridge.getFeeManagerMode()
+      feeManagerMode.should.be.equals(oneDirectionsModeHash)
+    })
   })
 
   describe('#feeManager_ExecuteAffirmation', async () => {