Don't warn when using browser globals

Create a script which scrapes web specifications to see what
variables/classes/functions are global in web browsers. Teach
quick-lint-js about these global variables to reduce false positives for
browser code.

Unfortunately, browsers have some global variables which might be common
in user code, such as 'length' and 'name'. In the future, we might
decide to trade some false positives for some false negatives. For now,
be conservative and err on the side of false negatives by including all
spec'd global variables.

I didn't check if the globals can be reassigned or shadowed. Err on the
side of false negatives by treating all these variables as writable and
shadowable.

Author: strager

docs/RELEASES.md

@@ -35,6 +35,8 @@ Beta release.
 
 ### Fixed
 
+* Using browser variables such as `document` and `window` no longer reports
+  undesired undeclared variable warnings
 * `with` statements and `eval` no longer cause spurious undeclared variable
   warnings (implemented by [Himanshu][])
 * `++a[0];` no longer reports an assignment-to-const-variable error if `a` was

src/CMakeLists.txt

@@ -53,6 +53,7 @@ quick_lint_js_add_library(
   file-handle.cpp
   file-path.cpp
   file.cpp
+  global-variables-browser.cpp
   gmo.cpp
   integer.cpp
   json.cpp
@@ -101,6 +102,7 @@ quick_lint_js_add_library(
   quick-lint-js/file-path.h
   quick-lint-js/file.h
   quick-lint-js/force-inline.h
+  quick-lint-js/global-variables.h
   quick-lint-js/gmo.h
   quick-lint-js/have.h
   quick-lint-js/integer.h

src/configuration.cpp

@@ -4,6 +4,7 @@
 #include <algorithm>
 #include <quick-lint-js/char8.h>
 #include <quick-lint-js/configuration.h>
+#include <quick-lint-js/global-variables.h>
 #include <quick-lint-js/lint.h>
 #include <quick-lint-js/narrow-cast.h>
 #include <quick-lint-js/unreachable.h>
@@ -23,6 +24,15 @@ ::simdjson::error_code get_bool_or_default(
 }
 
 const global_declared_variable_set& configuration::globals() noexcept {
+  if (this->add_global_group_browser_) {
+    for (const char8** it = global_variables_browser; *it; ++it) {
+      string8_view global(*it);
+      if (!this->should_remove_global_variable(global)) {
+        this->globals_.add_variable(global);
+      }
+    }
+  }
+
   if (this->add_global_group_ecmascript_) {
     const char8* writable_global_variables[] = {
         // ECMA-262 18.1 Value Properties of the Global Object
@@ -141,11 +151,16 @@ const std::optional<canonical_path>& configuration::config_file_path() const {
 }
 
 void configuration::reset_global_groups() {
+  this->add_global_group_browser_ = false;
   this->add_global_group_node_js_ = false;
   this->add_global_group_ecmascript_ = false;
 }
 
 bool configuration::add_global_group(string8_view group_name) {
+  if (group_name == u8"browser"sv) {
+    this->add_global_group_browser_ = true;
+    return true;
+  }
   if (group_name == u8"ecmascript"sv) {
     this->add_global_group_ecmascript_ = true;
     return true;