Android: Disable 'sincos' optimization to avoid 'osmesa' link errors.

third_party/mesa/mesa.gyp

Index: third_party/mesa/mesa.gyp
diff --git a/third_party/mesa/mesa.gyp b/third_party/mesa/mesa.gyp
index 1bd999d5a75377c8639df77e929701b2794099f0..610183de605e19f5cce3e05d8196e6a46f3e3a4c 100644
--- a/third_party/mesa/mesa.gyp
+++ b/third_party/mesa/mesa.gyp
@@ -557,6 +557,14 @@
                 '-Wstring-conversion',
               ],
             }],
+            ['OS=="android"', {
+                # Disable sincos() optimization to avoid a linker error
+                # since Android's math library doesn't have sincos().
+                # Either -fno-builtin-sin or -fno-builtin-cos works.
+                'cflags': [
+                '-fno-builtin-sin',
+                ],
+            }],
           ],
         },
         # Building this target will hide the native OpenGL shared library and