Crash log:
https://uberchromegw.corp.google.com/i/chromium.perf/builders/Mac%20HDD%20Perf%20%285%29/builds/2967/steps/service_worker.service_worker/logs/stdio

	Operating system: Mac OS X
	                  10.10.5 14F1909
	CPU: amd64
	     family 6 model 23 stepping 10
	     2 CPUs
	
	GPU: UNKNOWN
	
	Crash reason:  EXC_BAD_ACCESS / EXC_I386_GPFLT
	Crash address: 0x1088647f8
	Process uptime: 2 seconds
	
	Thread 18 (crashed)
	 0  Google Chrome Framework!ChromeMain + 0xda6568
	    rax = 0x00007f998a2dbb00   rdx = 0x00007f998a2dbb40
	    rcx = 0x00000001088647f0   rbx = 0x000000011b181ac8
	    rsi = 0x0000000000000002   rdi = 0x6000000000000000
	    rbp = 0x000000011b181a80   rsp = 0x000000011b181a80
	     r8 = 0x000000000018255b    r9 = 0x000000010f1d66e0
	    r10 = 0x0000000000000000   r11 = 0x0000000000000000
	    r12 = 0x000000010f1d66e9   r13 = 0x000000011b181c78
	    r14 = 0x000000010d1170ae   r15 = 0x00007f9988ccc2e0
	    rip = 0x00000001088647f8
	    Found by: given as instruction pointer in context
	 1  Google Chrome Framework!ChromeMain + 0x17e12e9
	    rbx = 0x000000011b181ac8   rbp = 0x000000011b181b40
	    rsp = 0x000000011b181a90   r12 = 0x000000010f1d66e9
	    r13 = 0x000000011b181c78   r14 = 0x000000010d1170ae
	    r15 = 0x00007f9988ccc2e0   rip = 0x000000010929f579
	    Found by: call frame info
	 2  Google Chrome Framework!ChromeMain + 0x18048b6
	    rbx = 0x000000011b181bb0   rbp = 0x000000011b181c00
	    rsp = 0x000000011b181b50   r12 = 0x00007f9988ccc2b8
	    r13 = 0x000000011b181c78   r14 = 0x00007f9988ccc1b0
	    r15 = 0x000000010f1d66e0   rip = 0x00000001092c2b46
	    Found by: call frame info
	 3  Google Chrome Framework!ChromeMain + 0x1804b7c
	    rbx = 0x00007f9988ccc1b0   rbp = 0x000000011b181c20
	    rsp = 0x000000011b181c10   r12 = 0x00007f9988ccc710
	    r13 = 0x000000011b181c78   r14 = 0x000000011b181c78
	    r15 = 0x2492492492492493   rip = 0x00000001092c2e0c
	    Found by: call frame info
	 4  Google Chrome Framework!ChromeMain + 0x1804ec3
	    rbx = 0x00007f9988ccc1b0   rbp = 0x000000011b181d50
	    rsp = 0x000000011b181c30   r12 = 0x00007f9988ccc710
	    r13 = 0x000000011b181c78   r14 = 0x000000011b181cc0
	    r15 = 0x2492492492492493   rip = 0x00000001092c3153
	    Found by: call frame info
	 5  Google Chrome Framework!ChromeMain + 0x18069d5
	    rbx = 0x000000011b181d88   rbp = 0x000000011b181dc0
	    rsp = 0x000000011b181d60   r12 = 0x00007f9988ccc710
	    r13 = 0x0000000000000001   r14 = 0x00000000ea5e1a01
	    r15 = 0x00007f9988ccc1b0   rip = 0x00000001092c4c65
	    Found by: call frame info
	 6  Google Chrome Framework!ChromeMain + 0x1821cf1
	    rbx = 0x000000011b181e60   rbp = 0x000000011b181e00
	    rsp = 0x000000011b181dd0   r12 = 0x00007f9988cf5a00
	    r13 = 0x00007f9988ccbfe0   r14 = 0x000000011b181dd0
	    r15 = 0x000000011b181e60   rip = 0x00000001092dff81
	    Found by: call frame info
	 7  Google Chrome Framework!ChromeMain + 0xc72234
	    rbx = 0x00007f9988ccbfe0   rbp = 0x000000011b181e20
	    rsp = 0x000000011b181e10   r12 = 0x00007f9988cf5a00
	    r13 = 0x00007f9988ccbfe0   r14 = 0x000000011b181e60
	    r15 = 0x000000011b181e60   rip = 0x00000001087304c4
	    Found by: call frame info
	 8  Google Chrome Framework!ChromeMain + 0xc722f4
	    rbx = 0x00007f9988ccbfe0   rbp = 0x000000011b181e50
	    rsp = 0x000000011b181e30   r12 = 0x00007f9988cf5a00
	    r13 = 0x00007f9988ccbfe0   r14 = 0x000000011b181e60
	    r15 = 0x000000011b181e60   rip = 0x0000000108730584
	    Found by: call frame info
....

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