Force-include assert.h for third_party/oboe
Force-include assert.h for third_party/oboe

Oboe uses assert but doesn't seem to include the header explicitly:

../../third_party/externals/oboe/src/flowgraph/resampler/PolyphaseResamplerStereo.cpp:25:5: error: use of undeclared identifier 'assert'
    assert(builder.getChannelCount() == STEREO);

Change-Id: Ib008ffaeade0b84196141102b956bc6e5606a468
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/383698
Reviewed-by: Jorge Betancourt <63f45fa27f6ebe96d0924e755262c906d4cb18db@google.com>
Commit-Queue: Florin Malita <a8262bf13ea8c26821e91ea9bca6740a77c96dcd@google.com>

aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,google/skia,google/skia,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,google/skia,aosp-mirror/platform_external_skia,google/skia,google/skia,google/skia,aosp-mirror/platform_external_skia,google/skia