Revert "Add Steve Johnson-style parser recovery rules:"

This reverts commit 97f8ee0d1b.

test/libsolidity/errorRecoveryTests/constructor_recovers.sol

@@ -1,20 +0,0 @@
-pragma solidity >=0.0.0;
-
-contract Error1 {
-  constructor() public {
-    balances[tx.origin] = ; // missing RHS.
-  }
-
-  // Without error recovery we stop due to the above error.
-  // Error recovery however recovers at the above ';'
-  // There should be an AST for the above, albeit with error
-  // nodes.
-
-  // This function parses properly and should give AST info.
-  function five() public view returns(uint) {
-    return 5;
-  }
-}
-// ----
-// ParserError: (95-96): Expected primary expression.
-// Warning: (95-96): Recovered in Statement at ';'.

test/libsolidity/errorRecoveryTests/contract_recovery.sol

@@ -1,7 +0,0 @@
-contract Errort6 {
-  using foo for  ; // missing type name
-}
-
-// ----
-// ParserError: (36-37): Expected type name
-// Warning: (59-60): Recovered in ContractDefinition at '}'.

test/libsolidity/errorRecoveryTests/do_not_delete_at_error.sol

@@ -1,13 +0,0 @@
-pragma solidity >=0.0.0;
-
-// Example to show why deleting the token at the
-// is bad when error recovery is in effect. Here, ")" is missing
-// and there is a ";" instead. That causes us to
-// not be able to synchronize to ';'. Advance again and
-// '}' is deleted and then we can't synchronize the contract.
-// There should be an an AST created this contract (with errors).
-contract Error2 {
-	mapping (address => uint balances; // missing ) before "balances"
-}
-// ----
-// ParserError: (417-425): Expected ')' but got identifier

test/libsolidity/errorRecoveryTests/error_to_eos.sol

@@ -1,23 +0,0 @@
-// Example which where scanning hits EOS, so we reset.
-// Here we recover in the contractDefinition.
-// There should be an an AST created this contract (with errors).
-contract Error2 {
-  mapping (address => uint balances) // missing ;
-}
-
-// There is no error in this contract
-contract SendCoin {
-  function sendCoin(address receiver, uint amount) public returns(bool sufficient) {
-    if (balances[msg.sender] < amount) return false;
-    balances[msg.sender] -= amount;
-    balances[receiver] += amount;
-    emit Transfer(msg.sender, receiver, amount);
-    return true;
-  }
-}
-
-// ----
-// ParserError: (212-220): Expected ')' but got identifier
-// ParserError: (220-221): Expected ';' but got ')'
-// ParserError: (220-221): Function, variable, struct or modifier declaration expected.
-// Warning: (235-236): Recovered in ContractDefinition at '}'.

test/libsolidity/errorRecoveryTests/missing_rhs.sol

@@ -1,11 +0,0 @@
-pragma solidity >=0.0.0;
-
-contract Error3 {
-	constructor() public {
-	    balances[tx.origin] = ; // missing RHS.
-	}
-
-}
-// ----
-// ParserError: (95-96): Expected primary expression.
-// Warning: (95-96): Recovered in Statement at ';'.

test/libsolidity/errorRecoveryTests/multiple_errors.sol

@@ -1,29 +0,0 @@
-// An example with multiple errors.
-// Most are caught by inserting an expected token.
-// However some us S C Johnson recovery to
-// skip over tokens.
-
-pragma solidity >=0.0.0;
-
-contract Error4 {
-  constructor() public {
-    balances[tx.origin] = 1 2; // missing operator
-  }
-
-  function sendCoin(address receiver, uint amount) public returns(bool sufficient) {
-    if (balances[msg.sender] < amount) return false;
-    balances[msg.sender] -= amount   // Missing ";"
-    balances[receiver] += amount   // Another missing ";"
-    emit Transfer(msg.sender  // truncated line
-    return true;
-  }
-
-
-}
-// ----
-// ParserError: (249-250): Expected ';' but got 'Number'
-// ParserError: (471-479): Expected ';' but got identifier
-// ParserError: (529-533): Expected ';' but got 'emit'
-// ParserError: (577-583): Expected ',' but got 'return'
-// ParserError: (577-583): Expected primary expression.
-// Warning: (588-589): Recovered in Statement at ';'.