Use D3DSWAPEFFECT_FLIPEX on Windows 7.
Use D3DSWAPEFFECT_FLIPEX on Windows 7.

Reduces frame rate jitters on Windows 7 reported in crbug.com/82925
Review URL: http://codereview.appspot.com/4517096

git-svn-id: a070b70d2b8c44c266a3870c0cddd9a0ee470458@654 736b8ea6-26fd-11df-bfd4-992fa37f6226

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