Do not dereference a NULL pointer when retrieving the base level image of an empty 2D array texture.
Do not dereference a NULL pointer when retrieving the base level image of an empty 2D array texture.

TRAC #23957

Signed-off-by: Geoff Lang
Signed-off-by: Shannon Woods

android-ia/platform_external_chromium_org_third_party_angle,vvuk/angle,ecoal95/angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,ppy/angle,vvuk/angle,MIPS/external-chromium_org-third_party-angle,bsergean/angle,nandhanurrevanth/angle,vvuk/angle,bsergean/angle,mybios/angle,crezefire/angle,ppy/angle,larsbergstrom/angle,mlfarrell/angle,ecoal95/angle,ecoal95/angle,jgcaaprom/android_external_chromium_org_third_party_angle,xin3liang/platform_external_chromium_org_third_party_angle,crezefire/angle,bsergean/angle,csa7mdm/angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,MSOpenTech/angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,ghostoy/angle,MIPS/external-chromium_org-third_party-angle,mrobinson/rust-angle,mikolalysenko/angle,nandhanurrevanth/angle,nandhanurrevanth/angle,MIPS/external-chromium_org-third_party-angle,mlfarrell/angle,ecoal95/angle,android-ia/platform_external_chromium_org_third_party_angle,mrobinson/rust-angle,android-ia/platform_external_chromium_org_third_party_angle,MSOpenTech/angle,mrobinson/rust-angle,mybios/angle,csa7mdm/angle,mybios/angle,csa7mdm/angle,ecoal95/angle,jgcaaprom/android_external_chromium_org_third_party_angle,jgcaaprom/android_external_chromium_org_third_party_angle,ppy/angle,mikolalysenko/angle,xin3liang/platform_external_chromium_org_third_party_angle,domokit/waterfall,ghostoy/angle,bsergean/angle,mikolalysenko/angle,csa7mdm/angle,nandhanurrevanth/angle,ghostoy/angle,mrobinson/rust-angle,xin3liang/platform_external_chromium_org_third_party_angle,xin3liang/platform_external_chromium_org_third_party_angle,larsbergstrom/angle,mlfarrell/angle,mikolalysenko/angle,mrobinson/rust-angle,crezefire/angle,domokit/waterfall,geekboxzone/lollipop_external_chromium_org_third_party_angle,android-ia/platform_external_chromium_org_third_party_angle,MSOpenTech/angle,jgcaaprom/android_external_chromium_org_third_party_angle,MIPS/external-chromium_org-third_party-angle,mlfarrell/angle,vvuk/angle,crezefire/angle,ghostoy/angle,larsbergstrom/angle,ppy/angle,larsbergstrom/angle,mybios/angle,MSOpenTech/angle