我需要删除ACRA以消除任何漏洞。我已经删除了app.gradle和MyApplication.java中的所有导入/编译。然而，当我尝试构建项目时，IDE给出了以下错误：

error: cannot find symbol class RequiresApi

这是我的app.gradle和MyApplication.java
app.gradle（我在依赖项中删除compile 'ch.acra：acra：4.9.2'后无法构建）

buildscript {
    (omitted)
}
apply plugin: 'com.android.application'
android {
    compileSdkVersion 22
    buildToolsVersion '27.0.3'
    defaultConfig {
        applicationId "******"
        minSdkVersion 17
        targetSdkVersion 22
        versionCode 6
        versionName "1.0.3"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    lintOptions {
        disable 'RestrictedApi'
    }
}
dependencies {
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:22.2.1'
    compile 'com.android.support:design:22.2.1'
    compile 'com.android.support:recyclerview-v7:22.2.1'
    compile 'com.journeyapps:zxing-android-embedded:3.0.1@aar'
    compile 'com.google.zxing:core:3.2.0'
    compile 'com.jakewharton:butterknife:8.0.1'
    annotationProcessor 'com.jakewharton:butterknife-compiler:8.0.1'
    compile 'net.zetetic:android-database-sqlcipher:3.5.7@aar'
    compile 'com.google.code.gson:gson:2.8.2'
    //compile 'ch.acra:acra:4.9.2' <- REMOVED ACRA
    compile "io.reactivex.rxjava2:rxjava:2.1.9"
    compile "io.reactivex.rxjava2:rxandroid:2.0.2"
}

MyApplication.java

package ******;
import android.app.Application;
public class MyApplication extends Application {
    private static MyApplication myApplication;
    public static MyApplication getInstance() {
        return myApplication;
    }
    public void onCreate() {
        super.onCreate();
        myApplication = this;
    }
}

我也试过清理我的项目和重建，但没有工作。当我放回ACRA时，项目照常构建。是IDE的问题吗？