Validate max proxy string length for proxySpec and
exclusionList using PolicySizeVerifier.

Bug: 445418705
Test: atest FrameworksServicesTests:com.android.server.devicepolicy.DevicePolicyManagerTest#testSetGlobalProxy_tooLongStrings()
Flag: EXEMPT BUGFIX
Cherrypick-From: https://googleplex-android-review.googlesource.com/q/commit:64a559cbc04fc61777989cff0b189f423323cfb5
Cherrypick-From: https://googleplex-android-review.googlesource.com/q/commit:0dc0cf0be184244582e501f1d0923c78f1ae6b3c
Merged-In: I97a26767ac42d87750bb98306c5d8b00ef39770e
Change-Id: I97a26767ac42d87750bb98306c5d8b00ef39770e
3 files changed