Men bu muammoni hal qildim.
Google doesn't update ADT any more, so when Eclipse export a project to gradle, it use an old gradle plugin version that Android Studio doesn't support.

First, you should check the version of gradle plugin that you have installed.
Open Android Studio's installation directory,then open the directory \gradle\m2repository\com\android\tools\build\gradle\
, you will see all version you have installed.

Then open Android Studio, open tab 'Project -> Gradle Scripts', Edit file build.gradle
, change the gradle plugin to newest version you have installed, such as 2.3.0:

[Majburiy] Ushbu qadam shart emas, lekin buni qilmasangiz, bu muammoni ko'rishingiz mumkin:
A problem occurred evaluating root project 'XXX'.
> org/gradle/initialization/BuildCompletionListener
Check the newest version of gradle you have installed at C:\Users\YOUR USER NAME\.gradle\wrapper\dists
.
Then open tab 'Project -> Gradle Scripts', edit file gradle-wrapper.properties
, modify the gradle version(attention: gradle, NOT gradle plugin) to the newest at the last line.

Finally, click Build - Clean Project
, done!
If it still warning "Gradle project sync failed...", just click Try Again
!

TUG'ILGAN, SABABLAR MENGA JAVOB BERADI YoRDAM BERADI, Grammatik xatolarsiz !!!