CCA: Rename isExist -> exists

The name isExist is grammatically incorrect. Change it to exists, which
is a more common name (for example, Node.js fs.exists, Python
os.path.exists, Ruby File.exists).

Bug: None
Test: cca.py tsc <board> with CL:4302331
Change-Id: Iba9e2631b44173dd08029c6a40f2ae85b594be8e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4321189
Auto-Submit: Pi-Hsun Shih <pihsun@chromium.org>
Reviewed-by: Wei Lee <wtlee@chromium.org>
Commit-Queue: Pi-Hsun Shih <pihsun@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1115562}

ash/webui/camera_app_ui/resources/js/gallerybutton.ts

@@ -165,7 +165,7 @@ export class GalleryButton implements ResultSaver {
 
     // Checks existence of cached cover photo.
     if (this.cover !== null) {
-      if (await dir.isExist(this.cover.name)) {
+      if (await dir.exists(this.cover.name)) {
         return;
       }
     }

ash/webui/camera_app_ui/resources/js/models/file_system_access_entry.ts

@@ -124,7 +124,7 @@ export interface DirectoryAccessEntry {
   /**
    * Checks if file or directory with the target name exists.
    */
-  isExist(name: string): Promise<boolean>;
+  exists(name: string): Promise<boolean>;
 
   /**
    * Create the file given by its |name|. If there is already a file with same
@@ -196,7 +196,7 @@ export class DirectoryAccessEntryImpl implements DirectoryAccessEntry {
     return new FileAccessEntry(handle, this);
   }
 
-  async isExist(name: string): Promise<boolean> {
+  async exists(name: string): Promise<boolean> {
     try {
       await this.getFile(name);
       return true;
@@ -216,7 +216,7 @@ export class DirectoryAccessEntryImpl implements DirectoryAccessEntry {
   async createFile(name: string): Promise<FileAccessEntry> {
     return createFileJobs.push(async () => {
       let uniqueName = name;
-      for (let i = 0; await this.isExist(uniqueName);) {
+      for (let i = 0; await this.exists(uniqueName);) {
         uniqueName = name.replace(/^(.*?)(?=\.)/, `$& (${++i})`);
       }
       const handle =
@@ -243,7 +243,7 @@ export class DirectoryAccessEntryImpl implements DirectoryAccessEntry {
   }
 
   async removeEntry(name: string): Promise<void> {
-    if (await this.isExist(name)) {
+    if (await this.exists(name)) {
       await this.handle.removeEntry(name);
     }
   }

ash/webui/camera_app_ui/resources/js/models/lazy_directory_entry.ts

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import {assert} from '../assert.js';
+
 import {
   DirectoryAccessEntry,
   FileAccessEntry,
@@ -67,11 +68,11 @@ class LazyDirectoryEntry implements DirectoryAccessEntry {
     return this.directory.getFile(name);
   }
 
-  async isExist(name: string): Promise<boolean> {
+  async exists(name: string): Promise<boolean> {
     if (this.directory === null) {
       return false;
     }
-    return this.directory.isExist(name);
+    return this.directory.exists(name);
   }
 
   async createFile(name: string): Promise<FileAccessEntry> {