SSE2 everywhere.

As of M35, Chrome will require SSE2 on Linux (it already did on Windows, and
requires SSSE3 on Macs).  Android already requires SSE2 for x86 chips.

This effectively just forces it on for 32-bit Linux builds; everyone else already had it.

BUG=skia:
R=reed@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/294963002

git-svn-id: http://skia.googlecode.com/svn/trunk@14800 2bbb7eff-a529-9590-31e7-b0007b416f81

gyp/common_conditions.gypi

@@ -14,6 +14,11 @@
       ],
     }],
 
+    # As of M35, Chrome requires SSE2 on x86 (and SSSE3 on Mac).
+    [ 'skia_arch_type == "x86"', {
+      'cflags': [ '-msse2' ],
+    }],
+
     [ 'skia_os == "win"',
       {
         'defines': [