Android / Blur Transformation: Fix leaked RenderScript objects

[projectgoav]

:sparkles: What kind of change does this PR introduce? (Bug fix, feature, docs update...)

Manually invoke Destroy() on allocated RenderScript objects within the (Android) BlurTransformation class. Previously the assumption was that .NET Dispose() would call this for us, but this does not seem to be the case.

By not doing this, the Android runtime complains about leaked resources.

[StrictMode] StrictMode policy violation: android.os.strictmode.LeakedClosableViolation: A resource was acquired at attached stack trace but never released. See java.io.Closeable for information on avoiding resource leaks.
[StrictMode]    at android.os.StrictMode$AndroidCloseGuardReporter.report(StrictMode.java:1987)
[StrictMode]    at dalvik.system.CloseGuard.warnIfOpen(CloseGuard.java:345)
[StrictMode]    at android.renderscript.BaseObj.finalize(BaseObj.java:149)
[StrictMode]    at java.lang.Daemons$FinalizerDaemon.doFinalize(Daemons.java:291)
[StrictMode]    at java.lang.Daemons$FinalizerDaemon.runInternal(Daemons.java:278)
[StrictMode]    at java.lang.Daemons$Daemon.run(Daemons.java:139)
[StrictMode]    at java.lang.Thread.run(Thread.java:920)
[StrictMode] Caused by: java.lang.Throwable: Explicit termination method 'destroy' not called
[StrictMode]    at dalvik.system.CloseGuard.openWithCallSite(CloseGuard.java:295)
[StrictMode]    at dalvik.system.CloseGuard.open(CloseGuard.java:263)
[StrictMode]    at android.renderscript.Script.< init > (Script.java:349)
[StrictMode]    at android.renderscript.ScriptIntrinsic.< init > (ScriptIntrinsic.java:34)
[StrictMode]    at android.renderscript.ScriptIntrinsicBlur.< init > (ScriptIntrinsicBlur.java:33)
[StrictMode]    at android.renderscript.ScriptIntrinsicBlur.create(ScriptIntrinsicBlur.java:53)
[StrictMode] StrictMode policy violation: android.os.strictmode.LeakedClosableViolation: A resource was acquired at attached stack trace but never released. See java.io.Closeable for information on avoiding resource leaks.
[StrictMode]    at android.os.StrictMode$AndroidCloseGuardReporter.report(StrictMode.java:1987)
[StrictMode]    at dalvik.system.CloseGuard.warnIfOpen(CloseGuard.java:345)
[StrictMode]    at android.renderscript.BaseObj.finalize(BaseObj.java:149)
[StrictMode]    at android.renderscript.Allocation.finalize(Allocation.java:436)
[StrictMode]    at java.lang.Daemons$FinalizerDaemon.doFinalize(Daemons.java:291)
[StrictMode]    at java.lang.Daemons$FinalizerDaemon.runInternal(Daemons.java:278)
[StrictMode]    at java.lang.Daemons$Daemon.run(Daemons.java:139)
[StrictMode]    at java.lang.Thread.run(Thread.java:920)
[StrictMode] Caused by: java.lang.Throwable: Explicit termination method 'destroy' not called
[StrictMode]    at dalvik.system.CloseGuard.openWithCallSite(CloseGuard.java:295)
[StrictMode]    at dalvik.system.CloseGuard.open(CloseGuard.java:263)
[StrictMode]    at android.renderscript.Allocation.< init > (Allocation.java:425)
[StrictMode]    at android.renderscript.Allocation.< init > (Allocation.java:429)
[StrictMode]    at android.renderscript.Allocation.createFromBitmap(Allocation.java:2837)

Note: Also removed a duplicated copy of the Blur code that was commented out. Happy to revert this change if required.

:arrow_heading_down: What is the current behavior?

:new: What is the new behavior (if this is a feature change)?

:boom: Does this PR introduce a breaking change?

:bug: Recommendations for testing

'StrictMode' was enabled by inserting the following to activity OnCreate

            StrictMode.SetVmPolicy(new StrictMode.VmPolicy.Builder(StrictMode.GetVmPolicy())
                                                          .DetectLeakedClosableObjects()
                                                          .Build());

:memo: Links to relevant issues/docs

:thinking: Checklist before submitting

• [ ] All projects build
• [x] Follows style guide lines
• [ ] Relevant documentation was updated
• [x] Rebased onto current develop