Fixed gl_FragCoord emulation for point sprites of size > 1 using VPOS semantic for x and y coordinates rather than previous per-vertex emulation when running on Shader Model 3.
Fixed gl_FragCoord emulation for point sprites of size > 1 using VPOS
semantic for x and y coordinates rather than previous per-vertex
emulation when running on Shader Model 3.

Verified fix in Chromium with test case from bug.

BUG=http://code.google.com/p/angleproject/issues/detail?id=71
TEST=test case from bug
TBR=nicolas (LGTM'd by dgkoch)

Review URL: http://codereview.appspot.com/2921041

git-svn-id: a070b70d2b8c44c266a3870c0cddd9a0ee470458@473 736b8ea6-26fd-11df-bfd4-992fa37f6226

shairai/angleproject,MIPS/external-chromium_org-third_party-angle_dx11,cvsuser-chromium/chromium-third-party_angle_dx11,shairai/angleproject,KTXSoftware/angleproject,vvuk/angle-old,shairai/angleproject,vvuk/angle-old,csa7mdm/angle,mrobinson/rust-angle,stammen/angleproject,csa7mdm/angle,android-ia/platform_external_chromium_org_third_party_angle,crezefire/angle,android-ia/platform_external_chromium_org_third_party_angle_dx11,ppy/angle,MSOpenTech/angle-win8.0,xin3liang/platform_external_chromium_org_third_party_angle_dx11,csa7mdm/angle,jgcaaprom/android_external_chromium_org_third_party_angle,ecoal95/angle,cantren/angleproject,MSOpenTech/angle-win8.0,themusicgod1/angleproject,bsergean/angle,mybios/angle,larsbergstrom/angle,cvsuser-chromium/chromium-third-party_angle_dx11,ghostoy/angle,xuxiandi/angleproject,mrobinson/rust-angle,mybios/angle,ppy/angle,crezefire/angle,mikolalysenko/angle,KTXSoftware/angleproject,ppy/angle,cvsuser-chromium/chromium-third-party_angle_dx11,geekboxzone/lollipop_external_chromium_org_third_party_angle,mrobinson/rust-angle,domokit/waterfall,vvuk/angle,RepublicMaster/angleproject,bsergean/angle,mikolalysenko/angle,mybios/angle,ghostoy/angle,MSOpenTech/angle,MIPS/external-chromium_org-third_party-angle,ecoal95/angle,nandhanurrevanth/angle,stammen/angleproject,themusicgod1/angleproject,jgcaaprom/android_external_chromium_org_third_party_angle,nandhanurrevanth/angle,MIPS/external-chromium_org-third_party-angle,pombreda/angleproject,KalebDark/angleproject,ppy/angle,KalebDark/angleproject,RepublicMaster/angleproject,pombreda/angleproject,xin3liang/platform_external_chromium_org_third_party_angle,mybios/angle,vvuk/angle-old,MIPS/external-chromium_org-third_party-angle_dx11,KTXSoftware/angleproject,geekboxzone/lollipop_external_chromium_org_third_party_angle,stammen/angleproject,android-ia/platform_external_chromium_org_third_party_angle_dx11,vvuk/angle,xuxiandi/angleproject,xuxiandi/angleproject,KalebDark/angleproject,nandhanurrevanth/angle,ehsan/angle,vvuk/angle,ghostoy/angle,shairai/angleproject,ehsan/angle,mlfarrell/angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,themusicgod1/angleproject,KalebDark/angleproject,xin3liang/platform_external_chromium_org_third_party_angle_dx11,mlfarrell/angle,larsbergstrom/angle,ecoal95/angle,RepublicMaster/angleproject,ecoal95/angle,crezefire/angle,android-ia/platform_external_chromium_org_third_party_angle_dx11,mrobinson/rust-angle,xuxiandi/angleproject,xin3liang/platform_external_chromium_org_third_party_angle,jgcaaprom/android_external_chromium_org_third_party_angle,android-ia/platform_external_chromium_org_third_party_angle,android-ia/platform_external_chromium_org_third_party_angle,ehsan/angle,mlfarrell/angle,cantren/angleproject,cvsuser-chromium/chromium-third-party_angle_dx11,themusicgod1/angleproject,android-ia/platform_external_chromium_org_third_party_angle_dx11,MIPS/external-chromium_org-third_party-angle,cantren/angleproject,vvuk/angle,MIPS/external-chromium_org-third_party-angle_dx11,ehsan/angle,MSOpenTech/angle-win8.0,ecoal95/angle,pombreda/angleproject,MSOpenTech/angle,MSOpenTech/angle-win8.0,ghostoy/angle,nandhanurrevanth/angle,xin3liang/platform_external_chromium_org_third_party_angle,KTXSoftware/angleproject,MIPS/external-chromium_org-third_party-angle,android-ia/platform_external_chromium_org_third_party_angle,stammen/angleproject,csa7mdm/angle,larsbergstrom/angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,mikolalysenko/angle,RepublicMaster/angleproject,mikolalysenko/angle,cantren/angleproject,MSOpenTech/angle,larsbergstrom/angle,MIPS/external-chromium_org-third_party-angle_dx11,pombreda/angleproject,xin3liang/platform_external_chromium_org_third_party_angle,bsergean/angle,crezefire/angle,domokit/waterfall,vvuk/angle-old,jgcaaprom/android_external_chromium_org_third_party_angle,MSOpenTech/angle,xin3liang/platform_external_chromium_org_third_party_angle_dx11,mrobinson/rust-angle,KTXSoftware/angleproject,mlfarrell/angle,xin3liang/platform_external_chromium_org_third_party_angle_dx11,bsergean/angle