Fix a bug in the webpack-sources patch that happens sometimes when using the webpack cache (#67928)

Author: mknichel

packages/next/src/build/webpack-build/impl.ts

@@ -188,7 +188,7 @@ export async function webpackBuildImpl(
   await runWebpackSpan.traceAsyncFn(async () => {
     if (config.experimental.webpackMemoryOptimizations) {
       stringBufferUtils.disableDualStringBufferCaching()
-      stringBufferUtils.enableStringInterning()
+      stringBufferUtils.enterStringInterningRange()
     }
 
     // Run the server compilers first and then the client
@@ -261,7 +261,7 @@ export async function webpackBuildImpl(
     }
 
     if (config.experimental.webpackMemoryOptimizations) {
-      stringBufferUtils.disableStringInterning()
+      stringBufferUtils.exitStringInterningRange()
     }
     inputFileSystem?.purge?.()
 

packages/next/src/compiled/webpack-sources3/index.js

@@ -453,9 +453,9 @@ declare module 'next/dist/compiled/loader-utils3'
 declare module 'next/dist/compiled/webpack-sources3' {
   interface StringBufferUtils {
     disableDualStringBufferCaching: () => boolean
-    disableStringInterning: () => boolean
     enableDualStringBufferCaching: () => boolean
-    enableStringInterning: () => boolean
+    enterStringInterningRange: () => boolean
+    exitStringInterningRange: () => boolean
   }
   export let stringBufferUtils: StringBufferUtils
 }