fix: revert add sourcemap for temaplate block

src/utils/descriptorCache.ts

@@ -4,7 +4,6 @@ import hash from 'hash-sum'
 import { parse, SFCDescriptor } from '@vue/component-compiler-utils'
 import * as vueTemplateCompiler from 'vue-template-compiler'
 import { ResolvedOptions } from '../index'
-import { RawSourceMap, SourceMapGenerator } from 'source-map'
 
 const cache = new Map<string, SFCDescriptor>()
 const prevCache = new Map<string, SFCDescriptor | undefined>()
@@ -22,24 +21,6 @@ export function createDescriptor(
     needMap: true,
   })
   // v2 hasn't generate template and customBlocks map
-  if (descriptor.template && !descriptor.template.src) {
-    descriptor.template.map = generateSourceMap(
-      filename,
-      source,
-      descriptor.template.content,
-      root
-    )
-  }
-  if (descriptor.customBlocks) {
-    descriptor.customBlocks.forEach((customBlock) => {
-      customBlock.map = generateSourceMap(
-        filename,
-        source,
-        customBlock.content,
-        root
-      )
-    })
-  }
   // ensure the path is normalized in a way that is consistent inside
   // project (relative to root) and on different systems.
   const normalizedPath = slash(path.normalize(path.relative(root, filename)))
@@ -72,37 +53,3 @@ export function getDescriptor(filename: string, errorOnMissing = true) {
 export function setDescriptor(filename: string, entry: SFCDescriptor) {
   cache.set(filename, entry)
 }
-
-const splitRE = /\r?\n/g
-const emptyRE = /^(?:\/\/)?\s*$/
-
-function generateSourceMap(
-  filename: string,
-  source: string,
-  generated: string,
-  sourceRoot: string
-): RawSourceMap {
-  const map = new SourceMapGenerator({
-    file: filename.replace(/\\/g, '/'),
-    sourceRoot: sourceRoot.replace(/\\/g, '/'),
-  })
-  const offset = source.split(generated).shift()!.split(splitRE).length - 1
-
-  map.setSourceContent(filename, source)
-  generated.split(splitRE).forEach((line, index) => {
-    if (!emptyRE.test(line)) {
-      map.addMapping({
-        source: filename,
-        original: {
-          line: index + 1 + offset,
-          column: 0,
-        },
-        generated: {
-          line: index + 1,
-          column: 0,
-        },
-      })
-    }
-  })
-  return JSON.parse(map.toString())
-}