Drop the defunct PartialStatementNode from v1 AST

Note that this is referring to the Handlebars `{{> ... }}` syntax,
not the (also defunct) Ember `{{partial ...}}` feature.

This had never worked in any modern versions of Ember (maybe v1+)
and the compiler doesn't do anything with it.

Author: chancancode

packages/@glimmer/syntax/lib/generation/printer.ts

@@ -96,7 +96,6 @@ export default class Printer {
     switch (node.type) {
       case 'MustacheStatement':
       case 'BlockStatement':
-      case 'PartialStatement':
       case 'MustacheCommentStatement':
       case 'CommentStatement':
       case 'TextNode':
@@ -161,8 +160,6 @@ export default class Printer {
         return this.MustacheStatement(statement);
       case 'BlockStatement':
         return this.BlockStatement(statement);
-      case 'PartialStatement':
-        return this.PartialStatement(statement);
       case 'MustacheCommentStatement':
         return this.MustacheCommentStatement(statement);
       case 'CommentStatement':
@@ -388,18 +385,6 @@ export default class Printer {
     this.buffer += ` as |${blockParams.join(' ')}|`;
   }
 
-  PartialStatement(partial: ASTv1.PartialStatement): void {
-    if (this.handledByOverride(partial)) {
-      return;
-    }
-
-    this.buffer += '{{>';
-    this.Expression(partial.name);
-    this.Params(partial.params);
-    this.Hash(partial.hash);
-    this.buffer += '}}';
-  }
-
   ConcatStatement(concat: ASTv1.ConcatStatement): void {
     if (this.handledByOverride(concat)) {
       return;

packages/@glimmer/syntax/lib/v1/nodes-v1.ts

@@ -93,15 +93,6 @@ export interface ElementModifierStatement extends BaseNode {
   hash: Hash;
 }
 
-export interface PartialStatement extends BaseNode {
-  type: 'PartialStatement';
-  name: PathExpression | SubExpression;
-  params: Expression[];
-  hash: Hash;
-  indent: string;
-  strip: StripFlags;
-}
-
 export interface CommentStatement extends BaseNode {
   type: 'CommentStatement';
   value: string;
@@ -167,7 +158,6 @@ export type StatementName =
   | 'MustacheStatement'
   | 'CommentStatement'
   | 'BlockStatement'
-  | 'PartialStatement'
   | 'MustacheCommentStatement'
   | 'TextNode'
   | 'ElementNode';
@@ -318,7 +308,6 @@ export type SharedNodes = {
   UndefinedLiteral: UndefinedLiteral;
   MustacheStatement: MustacheStatement;
   ElementModifierStatement: ElementModifierStatement;
-  PartialStatement: PartialStatement;
   AttrNode: AttrNode;
   ConcatStatement: ConcatStatement;
 };

packages/@glimmer/syntax/lib/v1/public-builders.ts

@@ -105,24 +105,6 @@ function buildElementModifier(
   };
 }
 
-function buildPartial(
-  name: ASTv1.PathExpression,
-  params?: ASTv1.Expression[],
-  hash?: ASTv1.Hash,
-  indent?: string,
-  loc?: SourceLocation
-): ASTv1.PartialStatement {
-  return {
-    type: 'PartialStatement',
-    name: name,
-    params: params || [],
-    hash: hash || buildHash([]),
-    indent: indent || '',
-    strip: { open: false, close: false },
-    loc: buildLoc(loc || null),
-  };
-}
-
 function buildComment(value: string, loc?: SourceLocation): ASTv1.CommentStatement {
   return {
     type: 'CommentStatement',
@@ -512,7 +494,6 @@ function buildLoc(...args: any[]): SourceSpan {
 export default {
   mustache: buildMustache,
   block: buildBlock,
-  partial: buildPartial,
   comment: buildComment,
   mustacheComment: buildMustacheComment,
   element: buildElement,

packages/@glimmer/syntax/lib/v1/visitor-keys.ts

@@ -9,7 +9,6 @@ const visitorKeys = {
   MustacheStatement: ['path', 'params', 'hash'],
   BlockStatement: ['path', 'params', 'hash', 'program', 'inverse'],
   ElementModifierStatement: ['path', 'params', 'hash'],
-  PartialStatement: ['name', 'params', 'hash'],
   CommentStatement: [],
   MustacheCommentStatement: [],
   ElementNode: ['attributes', 'modifiers', 'children', 'comments'],

packages/@glimmer/syntax/lib/v2/normalize.ts

@@ -323,8 +323,6 @@ class StatementNormalizer {
 
   normalize(node: ASTv1.Statement): ASTv2.ContentNode | ASTv2.NamedBlock {
     switch (node.type) {
-      case 'PartialStatement':
-        throw new Error(`Handlebars partial syntax ({{> ...}}) is not allowed in Glimmer`);
       case 'BlockStatement':
         return this.BlockStatement(node);
       case 'ElementNode':