fix Memory leak when using PlatformView [IOS] #24714

[ashawn]

This is my investigation, thanks!
https://juejin.im/post/5c6e6dd5f265da2dcf62821f

Fixes flutter/flutter#24714

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Thanks for your pull request. It looks like this may be your first contribution to a Google open source project (if not, look below for help). Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

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[ashawn]

I signed it!

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CLAs look good, thanks!

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CLAs look good, thanks!

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[amirh]

Thanks!

[amirh]

LGTM

[amirh]

cc @chinmaygarde

[amirh]

Will land on green

[chinmaygarde]

Good catch. Thanks. I wonder if we should provide a custom GL proc resolver with instrumented variants of the OpenGL methods where we can do sanity checks like this. There may be more instances of such leaks. CC @jason-simmons

[xujunquan]

@chinmaygarde it is a big problem to me ,can you give me some help

https://github.com/flutter/flutter/issues/37225