fonts: Fix UAF bug in SkRemoteGlyphCache.
fonts: Fix UAF bug in SkRemoteGlyphCache.

No reference to memory allocated from the serializer should be retained
after another allocation is made, since the vector can internally
realloc. In the case where a glyph is tooLargeForAtlas, we serialize the
path and still access the glyph after it, which could result in a UAF
bug.

R=14574f09dfa9b4e14759b88c3426a495a0e627b0@google.com

Bug: 874740
Change-Id: I33c048c154e53b89d68acd02d68718d7ec7b2388
Reviewed-on: https://skia-review.googlesource.com/147824
Commit-Queue: Mike Klein <14574f09dfa9b4e14759b88c3426a495a0e627b0@google.com>
Reviewed-by: Mike Klein <14574f09dfa9b4e14759b88c3426a495a0e627b0@google.com>

google/skia,HalCanary/skia-hc,rubenvb/skia,HalCanary/skia-hc,rubenvb/skia,google/skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,rubenvb/skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,HalCanary/skia-hc,aosp-mirror/platform_external_skia,rubenvb/skia,HalCanary/skia-hc,HalCanary/skia-hc,HalCanary/skia-hc,google/skia,google/skia,Hikari-no-Tenshi/android_external_skia,google/skia,rubenvb/skia,Hikari-no-Tenshi/android_external_skia,HalCanary/skia-hc,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,rubenvb/skia,google/skia,Hikari-no-Tenshi/android_external_skia,google/skia,HalCanary/skia-hc,rubenvb/skia,rubenvb/skia,Hikari-no-Tenshi/android_external_skia,Hikari-no-Tenshi/android_external_skia,rubenvb/skia,google/skia,aosp-mirror/platform_external_skia,google/skia,rubenvb/skia