Port all babel-parser changes from 2019-01-28 to 2019-03-26

[alangpierce]

Fixes #437

Details:
828169e61 Fix line continuation with Unicode line terminators (#9403)
🚫 We don't do escape parsing anyway.

4c4c22a31 Run prettier
🚫 Tools only.

00c3e3c8e Fixed link to @babel/parser's issues in README (#9427)
🚫 Docs only.

9eb010da5 Unify reserved word checking and update error messages (#9402)
🚫 Error handling only.

344d35bbe Simplify await and yield tracking in params (#9405)
🚫 Error handling only.

d896ce2b5 v7.3.2
🚫 Release only.

e03e5ba01 Add TypeScript definitions for parser plugin options. (#9457)
🚫 Types only.

07b0f22a3 Fix range for TypeScript optional parameter in arrow function (#9463)
🚫 AST only.

d1514f57b Typescript function destructured params (#9431)
🚫 Already fixed in my code (with a fix that I think is better).

2817844e8 Fix regression with let (#9477)
🚫 This doesn't seem to affect Sucrase.

d349b74a4 Better error output in parser tests (#9491)
🚫 Test only.

4ba998c5d Add importKind to spec
🚫 Types only.

d1fe2d05f v7.3.3
🚫 Release only.

058f05742 Also check AssignmentPatterns for export name (#9521)
🚫 Error handling only.

a1ea765b9 Make tests spec compliant and avoid duplicate declarations in input files (#9522)
🚫 Test only.

dd8b700a2 Parenthesized expressions (#8025)
🚫 New feature that won't go into Sucrase.

9f3457797 Fix TypeScript parsers missing token check (#9571) (#9572)
✅ Added new check with test.

fc1ea7f49 Revert "Parenthesized expressions (#8025)"
🚫 New feature that won't go into Sucrase.

1f6454cc9 v7.3.4
🚫 Release only.

a7391144b Introduce scope tracking in the parser (#9493)
🚫 Looks like this is just for error handling.

e6c1065d1 Fix strict mode prescanning with EmptyStatement (#9585)
🚫 We don't detect strict mode.

d0e196d21 Treat for loop body as part of loop scope (#9586)
🚫 Scopes not tracked in Sucrase in the same way.

0345c1bc1 Use for..of Object.keys instead of for..in (#9518)
🚫 Not relevant for Sucrase.

244e4580e Remove always false param allowExpressionBody (#9591)
✅ Removed, plus removed some other unnecessary params.

a029071b8 [TS] Correctly forget awaits after parsing async arrows with type args (#9593)
🚫 Doesn't come up in Sucrase.

e883ff295 Merge pull request #9597 from danez/Update-charcodes
🚫 Mostly just changes in types.

43eed1ac9 Check exported bindings are defined (#9589)
🚫 Error handling only.

5cb280f98 Fix scope check for 2nd+ lexical bindings (#9600)
🚫 Error handling only.

208195f42 Disallow duplicate params in methods (#9599)
🚫 Error handling only.

98ab1b642 Refactor parsing object members (#9607)
🚫 I won't try to port this refactor for now.

f13f4adcb [TS] Disallow type casts in arrow parameters (#9612)
🚫 Error handling only.

17f4195bc Allow any reserved word in export {} from specifiers (#9616)
🚫 Already works in Sucrase.

c60c4dd37 Partial Application Syntax: Stage 1 (#9343)
✅ Added basic parsing for ? expression.

d832c0f43 Add parser support for placeholders (#9364)
🚫 I won't include this feature in Sucrase.

54ba6d80c Update identifier parsing per Unicode v12 (#9637)
🚫 Sucrase doesn't need this validation.

29999007f Disallow escape sequences in contextual keywords (#9618)
🚫 We don't support identifier escape sequences in the first place.

fba5655a4 Parenthesized expressions (#8025)
🚫 I won't include this feature in Sucrase.

e53be4b38 [TS] Allow context type annotation on getters/setters (#9641)
🚫 Bug in validation that Sucrase doesn't do.

d8a532983 Reorganize token types and use a map for them (#9645)
🚫 Not really relevant for current Sucrase code.

cf4bd8bb8 Remove input and length from state (#9646)
🚫 Not relevant for Sucrase.

29cd27b54 Partial application plugin (#9474)
🚫 Tests only.

25a3825a1 TypeScript Constant contexts (#9534)
✅ Added test, already works from previous change to make it an identifier.

cc4560842 Add readonly to TypeScript type modifier (#9529)
✅ Added new case with test.

48d66eb64 Correctly parse TS TypeAssertions around arrow functions (#9699)
🚫 AST only, I think.

f1328fb91 v7.4.0
🚫 Release only.

ab41cb2cd Fix scope checks with enabled flow plugin (#9719)
🚫 Scope code doesn't exist in Sucrase.

2201fd839 Modules might be in loose mode when checking for undecl exports (#9725)
🚫 Sucrase always uses strict mode.

7dea0f23d v7.4.2
🚫 Release only.

ef0722b4b Fix compatibility between estree and TS plugin (#9700)
🚫 Sucrase doesn't support estree mode.

aaefc83a6 Allow HTML comments on first line (#9760)
🚫 Unclear what this is needed for, but doesn't seem important in Sucrase.

d720c6cff Explicit labels for tokenTypes (#9761)
🚫 Internal change.

444daf922 Optimize parseBindingAtom code to get better error messages (#9762)
🚫 Error checking only.

2867bbf19 [typescript] parsing template literal as type (#9748)
✅ Added new case with test.

7f4427432 Parse right-hand-side of for/of as an assignment expression (#9767)
🚫 Error checking only.

6bc9e7ebd Correctly check for-in and for-of loop for invalid left-hand side (#9768)
🚫 Error checking only.

60d7e940e Fix merge error
🚫 Not relevant to Sucrase.

[codecov-io]

Codecov Report

Merging #440 into master will increase coverage by 0.04%.
The diff coverage is 90%.

@@            Coverage Diff             @@
##           master     #440      +/-   ##
==========================================
+ Coverage   81.09%   81.14%   +0.04%     
==========================================
  Files          49       49              
  Lines        5370     5134     -236     
  Branches     1204     1200       -4     
==========================================
- Hits         4355     4166     -189     
+ Misses        716      672      -44     
+ Partials      299      296       -3

Impacted Files	Coverage Δ
src/parser/plugins/flow.ts	64.41% <75%> (+1.91%)	⬆️
src/parser/plugins/typescript.ts	79.26% <87.5%> (+0.31%)	⬆️
src/parser/traverser/statement.ts	82.2% <90%> (+1.08%)	⬆️
src/parser/traverser/expression.ts	82.81% <94.44%> (-0.49%)	⬇️
src/util/getDeclarationInfo.ts	80% <0%> (-20%)	⬇️
src/parser/index.ts	77.77% <0%> (-7.94%)	⬇️
src/index.ts	82.85% <0%> (-6.51%)	⬇️
src/computeSourceMap.ts	83.33% <0%> (-5.56%)	⬇️
src/util/getNonTypeIdentifiers.ts	94.44% <0%> (-5.56%)	⬇️
src/util/getTSImportedNames.ts	81.57% <0%> (-3.79%)	⬇️
... and 20 more

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