Fix Rust keyword inconsistency (#6794)

* Make Rust keyword escaping more consistent

* fix comment

* git clang format

Co-authored-by: Casper Neo <cneo@google.com>

tests/keyword_test/public_generated.rs

@@ -0,0 +1,89 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+extern crate flatbuffers;
+use std::mem;
+use std::cmp::Ordering;
+use self::flatbuffers::{EndianScalar, Follow};
+use super::*;
+#[deprecated(since = "2.0.0", note = "Use associated constants instead. This will no longer be generated in 2021.")]
+pub const ENUM_MIN_PUBLIC: i32 = 0;
+#[deprecated(since = "2.0.0", note = "Use associated constants instead. This will no longer be generated in 2021.")]
+pub const ENUM_MAX_PUBLIC: i32 = 0;
+#[deprecated(since = "2.0.0", note = "Use associated constants instead. This will no longer be generated in 2021.")]
+#[allow(non_camel_case_types)]
+pub const ENUM_VALUES_PUBLIC: [public; 1] = [
+  public::NONE,
+];
+
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
+#[repr(transparent)]
+pub struct public(pub i32);
+#[allow(non_upper_case_globals)]
+impl public {
+  pub const NONE: Self = Self(0);
+
+  pub const ENUM_MIN: i32 = 0;
+  pub const ENUM_MAX: i32 = 0;
+  pub const ENUM_VALUES: &'static [Self] = &[
+    Self::NONE,
+  ];
+  /// Returns the variant's name or "" if unknown.
+  pub fn variant_name(self) -> Option<&'static str> {
+    match self {
+      Self::NONE => Some("NONE"),
+      _ => None,
+    }
+  }
+}
+impl std::fmt::Debug for public {
+  fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+    if let Some(name) = self.variant_name() {
+      f.write_str(name)
+    } else {
+      f.write_fmt(format_args!("<UNKNOWN {:?}>", self.0))
+    }
+  }
+}
+impl<'a> flatbuffers::Follow<'a> for public {
+  type Inner = Self;
+  #[inline]
+  fn follow(buf: &'a [u8], loc: usize) -> Self::Inner {
+    let b = unsafe {
+      flatbuffers::read_scalar_at::<i32>(buf, loc)
+    };
+    Self(b)
+  }
+}
+
+impl flatbuffers::Push for public {
+    type Output = public;
+    #[inline]
+    fn push(&self, dst: &mut [u8], _rest: &[u8]) {
+        unsafe { flatbuffers::emplace_scalar::<i32>(dst, self.0); }
+    }
+}
+
+impl flatbuffers::EndianScalar for public {
+  #[inline]
+  fn to_little_endian(self) -> Self {
+    let b = i32::to_le(self.0);
+    Self(b)
+  }
+  #[inline]
+  #[allow(clippy::wrong_self_convention)]
+  fn from_little_endian(self) -> Self {
+    let b = i32::from_le(self.0);
+    Self(b)
+  }
+}
+
+impl<'a> flatbuffers::Verifiable for public {
+  #[inline]
+  fn run_verifier(
+    v: &mut flatbuffers::Verifier, pos: usize
+  ) -> Result<(), flatbuffers::InvalidFlatbuffer> {
+    use self::flatbuffers::Verifiable;
+    i32::run_verifier(v, pos)
+  }
+}
+
+impl flatbuffers::SimpleToVerifyInSlice for public {}